#include "bits/stdc++.h"
using namespace std;
#ifdef _DEBUG
#include "dump.hpp"
#else
#define dump(...)
#endif

//#define int long long
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define all(c) begin(c),end(c)
const int INF = sizeof(int) == sizeof(long long) ? 0x3f3f3f3f3f3f3f3fLL : 0x3f3f3f3f;
const int MOD = 1'000'000'007;
template<class T> bool chmax(T &a, const T &b) { if (a < b) { a = b; return true; } return false; }
template<class T> bool chmin(T &a, const T &b) { if (b < a) { a = b; return true; } return false; }

template<int MOD>
struct ModInt {
	static const int kMod = MOD;
	unsigned x;
	ModInt() : x(0) {}
	ModInt(signed sig) { int sigt = sig % kMod; if (sigt < 0) sigt += kMod; x = sigt; }
	ModInt(signed long long sig) { int sigt = sig % kMod; if (sigt < 0) sigt += kMod; x = sigt; }
	int get() const { return (int)x; }

	ModInt &operator+=(ModInt that) { if ((x += that.x) >= kMod) x -= kMod; return *this; }
	ModInt &operator-=(ModInt that) { if ((x += kMod - that.x) >= kMod) x -= kMod; return *this; }
	ModInt &operator*=(ModInt that) { x = (unsigned long long)x * that.x % kMod; return *this; }
	ModInt &operator/=(ModInt that) { return *this *= that.inverse(); }

	ModInt operator+(ModInt that) const { return ModInt(*this) += that; }
	ModInt operator-(ModInt that) const { return ModInt(*this) -= that; }
	ModInt operator*(ModInt that) const { return ModInt(*this) *= that; }
	ModInt operator/(ModInt that) const { return ModInt(*this) /= that; }

	ModInt inverse() const {
		signed a = x, b = kMod, u = 1, v = 0;
		while (b) {
			signed t = a / b;
			a -= t * b; swap(a, b);
			u -= t * v; swap(u, v);
		}
		if (u < 0) u += kMod;
		ModInt res; res.x = (unsigned)u;
		return res;
	}
};
template<int MOD>
ostream &operator << (ostream &os, const ModInt<MOD> &m) { return os << m.x; }
template<int MOD>
istream &operator >> (istream &is, ModInt<MOD> &m) { signed long long s; is >> s; m = ModInt<MOD>(s); return is; };

using mint = ModInt<1000000007>;

mint pow(mint a, unsigned long long k) {
	mint r = 1;
	while (k) {
		if (k & 1) r *= a;
		a *= a;
		k >>= 1;
	}
	return r;
}

vector<mint> fact, factinv;
void precomputeFactorial(int N) {
	N = min(N, mint::kMod - 1);
	fact.resize(N + 1); factinv.resize(N + 1);
	fact[0] = 1;
	rep(i, 1, N + 1) fact[i] = fact[i - 1] * i;
	factinv[N] = fact[N].inverse();
	for (int i = N; i >= 1; i--) factinv[i - 1] = factinv[i] * i;
}
mint combi(int n, int r) {
	if (n >= mint::kMod)
		return combi(n % mint::kMod, r % mint::kMod) * combi(n / mint::kMod, r / mint::kMod);
	return r > n ? 0 : fact[n] * factinv[n - r] * factinv[r];
}

using ll = mint;
struct LazySegmentTree {
private:
	int n;
	vector<ll> node, lazy;

public:
	LazySegmentTree(vector<ll> v) {
		int sz = (int)v.size();
		n = 1; while (n < sz) n *= 2;
		node.resize(2 * n - 1);
		lazy.resize(2 * n - 1, 0);

		for (int i = 0; i < sz; i++) node[i + n - 1] = v[i];
		for (int i = n - 2; i >= 0; i--) node[i] = node[i * 2 + 1] + node[i * 2 + 2];
	}

	void eval(int k, int l, int r) {
		if (lazy[k].get() != 0) {
			node[k] += lazy[k];
			if (r - l > 1) {
				lazy[2 * k + 1] += lazy[k] / 2;
				lazy[2 * k + 2] += lazy[k] / 2;
			}
			lazy[k] = 0;
		}
	}

	void add(int a, int b, ll x, int k = 0, int l = 0, int r = -1) {
		if (r < 0) r = n;
		eval(k, l, r);
		if (b <= l || r <= a) return;
		if (a <= l && r <= b) {
			lazy[k] += x * (r - l);
			eval(k, l, r);
		}
		else {
			add(a, b, x, 2 * k + 1, l, (l + r) / 2);
			add(a, b, x, 2 * k + 2, (l + r) / 2, r);
			node[k] = node[2 * k + 1] + node[2 * k + 2];
		}
	}

	ll getsum(int a, int b, int k = 0, int l = 0, int r = -1) {
		if (r < 0) r = n;
		eval(k, l, r);
		if (b <= l || r <= a) return 0;
		if (a <= l && r <= b) return node[k];
		ll vl = getsum(a, b, 2 * k + 1, l, (l + r) / 2);
		ll vr = getsum(a, b, 2 * k + 2, (l + r) / 2, r);
		return vl + vr;
	}
};

signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	int N, M, K; cin >> N >> M >> K;
	vector<int> L(M), R(M); rep(i, 0, M) {
		cin >> L[i] >> R[i];
		L[i], R[i];
		L[i]--;
	}

	vector<ll> v(N, 0);
	v[0] = 1;
	LazySegmentTree lst(v);
	LazySegmentTree lst2(lst);

	rep(k, 0, K) {
		lst = lst2;
		lst2 = LazySegmentTree(vector<ll>(N, 0));

		rep(i, 0, M) {
			ll sum = lst.getsum(L[i], R[i]);
			dump(lst2.getsum(0, N));
			dump(sum);
			lst2.add(L[i], R[i], sum);
		}
	}

	cout << lst2.getsum(N - 1, N) << endl;

	return 0;
}