import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.math.BigDecimal;
import java.text.DecimalFormat;
import java.util.AbstractMap;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Deque;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;

import static java.util.Comparator.*;				

public class Main {
	
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        MyInput in = new MyInput(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        
        Solver solver = new Solver();
        solver.solve(1, in, out);
        
        out.close();
    }
    
    // ======================================================================
    
    static class Solver {
    	int MOD = 1000000007;
    	int N, M, K;
    	int[] L, R;
    	// 階　→　エレベータのリスト
    	Map<Integer, List<Integer>> map = new HashMap<Integer, List<Integer>>();
    	
    	// エレベータを使った回数　と　現在の階　を引数とする
    	long[][] dp;
    	public long calc(int cnt, int floor, PrintWriter out) {
//    		out.println("start  cnt = " + cnt + "  floor = " + floor);
    		if(dp[cnt][floor] != -1) {
//    			out.println("1 return  dp[" + cnt + "][" + floor + "] = " + dp[cnt][floor]);
    			return dp[cnt][floor];
    		}
    		if(cnt == K) {
    			if(floor == N) {
//    				out.println("2 return 1 !!!");
    				return 1;
    			} else {
//    				out.println("2 return 0");
    				return 0;
    			}
    		}
    		long ans = 0;
    		List<Integer> list = map.get(floor);	// エレベータのリスト
    		if(list != null) {
        		for(int m : list) {
        			for(int i=L[m]; i <= R[m]; i++) {
        	    		ans += calc(cnt + 1, i, out);
        	    		ans %= MOD;
        			}
        		}
    		}
    		dp[cnt][floor] = ans;
//    		out.println("end   cnt = " + cnt + "  floor = " + floor + "  -->  ans = " + ans);
    		return ans;
    	}
    	
    	public void solve(int testNumber, MyInput in, PrintWriter out) {
    		N = in.nextInt();
    		M = in.nextInt();
    		K = in.nextInt();
    		L = new int[M];
    		R = new int[M];
    		List<Integer> list = null;
    		for(int i=0; i < M; i++) {
    			L[i] = in.nextInt();
    			R[i] = in.nextInt();
    			//　各階で使えるエレベータを登録する
    			for(int j=L[i]; j <= R[i]; j++){
    				list = map.get(j);
    				if(list == null) {
    					list = new ArrayList<Integer>();
    					map.put(j, list);
    				}
    				list.add(i);
    			}
    		}
    		dp = new long[K+1][N+1];
    		for(int i=0; i < K+1; i++)
    			for(int j=0; j < N+1; j++)
    				dp[i][j] = -1;
    		out.println(calc(0, 1, out));
    	}
    }
    static class PPP {
    	public int key, val;
    	public PPP(int key, int val) {
    		this.key = key;
    		this.val = val;
    	}
		public int getKey() {
			return key;
		}
		public void setKey(int key) {
			this.key = key;
		}
		public int getVal() {
			return val;
		}
		public void setVal(int val) {
			this.val = val;
		}
    }
    // ======================================================================
    static class Pair<K, V> extends AbstractMap.SimpleEntry<K, V> {
        /** serialVersionUID. */
        private static final long serialVersionUID = 6411527075103472113L;

        public Pair(final K key, final V value) {
            super(key, value);
        }
     }    
    static class MyInput {
        private final BufferedReader in;
        private static int pos;
        private static int readLen;
        private static final char[] buffer = new char[1024 * 8];
        private static char[] str = new char[500 * 8 * 2];
        private static boolean[] isDigit = new boolean[256];
        private static boolean[] isSpace = new boolean[256];
        private static boolean[] isLineSep = new boolean[256];
 
        static {
            for (int i = 0; i < 10; i++) {
                isDigit['0' + i] = true;
            }
            isDigit['-'] = true;
            isSpace[' '] = isSpace['\r'] = isSpace['\n'] = isSpace['\t'] = true;
            isLineSep['\r'] = isLineSep['\n'] = true;
        }
 
        public MyInput(InputStream is) {
            in = new BufferedReader(new InputStreamReader(is));
        }
 
        public int read() {
            if (pos >= readLen) {
                pos = 0;
                try {
                    readLen = in.read(buffer);
                } catch (IOException e) {
                    throw new RuntimeException();
                }
                if (readLen <= 0) {
                    throw new MyInput.EndOfFileRuntimeException();
                }
            }
            return buffer[pos++];
        }
 
        public int nextInt() {
            int len = 0;
            str[len++] = nextChar();
            len = reads(len, isSpace);
            int i = 0;
            int ret = 0;
            if (str[0] == '-') {
                i = 1;
            }
            for (; i < len; i++) ret = ret * 10 + str[i] - '0';
            if (str[0] == '-') {
                ret = -ret;
            }
            return ret;
        }
 
        public long nextLong() {
            int len = 0;
            str[len++] = nextChar();
            len = reads(len, isSpace);
            int i = 0;
            long ret = 0L;
            if (str[0] == '-') {
                i = 1;
            }
            for (; i < len; i++) ret = ret * 10 + str[i] - '0';
            if (str[0] == '-') {
                ret = -ret;
            }
            return ret;
        }
 
       public String nextString() {
        	String ret = new String(nextDChar()).trim();
            return ret;
        }
 
        public char[] nextDChar() {
            int len = 0;
            len = reads(len, isSpace);
            char[] ret = new char[len + 1];
            for (int i=0; i < len; i++)		ret[i] = str[i];
            ret[len] = 0x00;
            return ret;
        }
 
        public char nextChar() {
            while (true) {
                final int c = read();
                if (!isSpace[c]) {
                    return (char) c;
                }
            }
        }
 
        int reads(int len, boolean[] accept) {
            try {
                while (true) {
                    final int c = read();
                    if (accept[c]) {
                        break;
                    }
                    if (str.length == len) {
                        char[] rep = new char[str.length * 3 / 2];
                        System.arraycopy(str, 0, rep, 0, str.length);
                        str = rep;
                    }
                    str[len++] = (char) c;
                }
            } catch (MyInput.EndOfFileRuntimeException e) {
            }
            return len;
        }
 
        static class EndOfFileRuntimeException extends RuntimeException {
        }
    }
}