using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;
using System.Runtime.Intrinsics.Arm;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var c = NList;
        var (n, m, k) = (c[0], c[1], c[2]);
        var map = NArr(m);

        var mod = 1_000_000_007;
        var dp1 = new long[n];
        dp1[0] = 1;
        var dp2 = new long[n];
        for (var i = 0; i < k; ++i)
        {
            dp2[0] = 0;
            for (var j = 1; j < n; ++j)
            {
                dp1[j] = (dp1[j] + dp1[j - 1]) % mod;
                dp2[j] = 0;
            }
            for (var j = 0; j < m; ++j)
            {
                var sum = dp1[map[j][1] - 1];
                if (map[j][0] > 1) sum = (sum + mod - dp1[map[j][0] - 2]) % mod;
                dp2[map[j][0] - 1] = (dp2[map[j][0] - 1] + sum) % mod;
                if (map[j][1] < n) dp2[map[j][1]] = (dp2[map[j][1]] + mod - sum) % mod;
            }
            for (var j = 1; j < n; ++j) dp2[j] = (dp2[j] + dp2[j - 1]) % mod;
            (dp1, dp2) = (dp2, dp1);
        }
        WriteLine(dp1[^1]);
    }
}