import sys

sys.setrecursionlimit(10**6)
int1 = lambda x: int(x)-1
p2D = lambda x: print(*x, sep="\n")
def II(): return int(sys.stdin.buffer.readline())
def MI(): return map(int, sys.stdin.buffer.readline().split())
def MF(): return map(float, sys.stdin.buffer.readline().split())
def MI1(): return map(int1, sys.stdin.buffer.readline().split())
def LI(): return list(map(int, sys.stdin.buffer.readline().split()))
def LI1(): return list(map(int1, sys.stdin.buffer.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def BI(): return sys.stdin.buffer.readline().rstrip()
def SI(): return sys.stdin.buffer.readline().rstrip().decode()
dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
inf = 10**16
# md = 998244353
md = 10**9+7

n, m, k = MI()
lr = [(l-1, r) for l, r in LLI(m)]
dp = [0]*(n+1)
dp[0] = 1

for _ in range(k):
    cs = [0]*(n+1)
    for i in range(n):
        cs[i+1] = (dp[i]+cs[i])%md
    dp = [0]*(n+1)
    for l, r in lr:
        cur = cs[r]-cs[l]
        dp[l] += cur
        dp[r] -= cur
    for i in range(n):
        dp[i+1] = (dp[i+1]+dp[i])%md

print(dp[n-1])