import sys
import pypyjit
import itertools
import heapq
import math
from collections import deque, defaultdict
import bisect

input = sys.stdin.readline
sys.setrecursionlimit(10 ** 6)
pypyjit.set_param('max_unroll_recursion=-1')


def index_lt(a, x):
    'return largest index s.t. A[i] < x or -1 if it does not exist'
    return bisect.bisect_left(a, x) - 1


def index_le(a, x):
    'return largest index s.t. A[i] <= x or -1 if it does not exist'
    return bisect.bisect_right(a, x) - 1


def index_gt(a, x):
    'return smallest index s.t. A[i] > x or len(a) if it does not exist'
    return bisect.bisect_right(a, x)


def index_ge(a, x):
    'return smallest index s.t. A[i] >= x or len(a) if it does not exist'
    return bisect.bisect_left(a, x)


N, M, K = map(int, input().split())
E = [tuple(map(lambda x: int(x) - 1, input().split())) for _ in range(M)]
mod = 10 ** 9 + 7

dp = [[0 for _ in range(N)] for _ in range(K + 1)]
S = [[0 for _ in range(N)] for _ in range(K + 1)]
dp[0][0] = 1
for j in range(N):
    S[0][j] = 1

for i in range(K):
    for l, r in E:
        s = S[i][r] - (S[i][l - 1] if l > 0 else 0)
        dp[i + 1][l] += s
        if r + 1 < N:
            dp[i + 1][r + 1] -= s

    for j in range(1, N):
        dp[i + 1][j] += dp[i + 1][j - 1]
        dp[i + 1][j] %= mod

    S[i + 1][0] = dp[i + 1][0]
    for j in range(1, N):
        S[i + 1][j] = dp[i + 1][j] + S[i + 1][j - 1]
        S[i + 1][j] %= mod
print(dp[K][N - 1])