n, m, k = map(int, input().split())
mod = 10**9+7
L = [[0, 0] for i in range(m)]
for i in range(m):
    l, r = map(int, input().split())
    L[i][0] = l-1
    L[i][1] = r-1

dp = [[0]*n for _ in range(k+1)]
dp[0][0] = 1
from itertools import accumulate
for i in range(k):
    cum = [0] + dp[i]
    cum = list(accumulate(cum))
    imos = [0]*(n+1)
    for j in range(m):
        l, r = L[j]
        imos[l] += cum[r+1]%mod- cum[l]%mod
        imos[r+1] -= cum[r+1]%mod - cum[l]%mod
    cum = list(accumulate(imos))
    dp[i+1] = cum
#print(dp)
print(dp[k][n-1]%mod)