n, m, k = map(int, input().split())
info = [list(map(int, input().split())) for i in range(m)]
MOD = 10**9 + 7

for i in range(m):
    info[i][0] = info[i][0] - 1
    info[i][1] = info[i][1] - 1

# dp[i][j] := i回乗った時点でj階にいるときの通り数
dp = [[0]*n for _ in range(k+1)]
dp_sum = [0]*(n+1)
dp[0][0] = 1


for move_times in range(k):
    for floor in range(n):
        dp_sum[floor + 1] = dp_sum[floor] + dp[move_times][floor]
        dp_sum[floor + 1] %= MOD
    imos = [0]*(n+1)
    for elev in range(m): 
        imos[info[elev][0]] +=  dp_sum[info[elev][1] + 1] - dp_sum[info[elev][0]]
        imos[info[elev][1] + 1] -=  dp_sum[info[elev][1] + 1] - dp_sum[info[elev][0]]

    for floor in range(n):
        imos[floor + 1] = imos[floor + 1] + imos[floor]
        imos[floor + 1] %= MOD

    for floor in range(n):
         dp[move_times + 1][floor] += imos[floor]
         dp[move_times + 1][floor] %= MOD

print(dp[k][n-1])