use std::thread::current;


const MOD: isize = 1e9 as isize + 7;

fn main() {
    let mut nmk = String::new();
    std::io::stdin().read_line(&mut nmk).ok();
    let nmk: Vec<usize> = nmk.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
    let n = nmk[0];
    let m = nmk[1];
    let k = nmk[2];
    let mut lines = Vec::with_capacity(m);
    for _ in 0..m {
        let mut lr = String::new();
        std::io::stdin().read_line(&mut lr).ok();
        let lr: Vec<usize> = lr.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
        let l = lr[0]-1;
        let r = lr[1]-1;
        lines.push((l, r));
    }

    let mut dp = vec![0isize; n];
    dp[0] = 1;
    for _ in 0..k {
        let mut prev_sum = vec![0isize; n+1];
        for i in 0..n {
            prev_sum[i+1] = prev_sum[i] + dp[i];
            prev_sum[i+1] %= MOD;
        }
        let mut current_sum = vec![0isize; n+1];
        for &(l, r) in lines.iter() {
            let val = (MOD + prev_sum[r+1] - prev_sum[l]) % MOD;
            current_sum[l] += val;
            current_sum[r+1] -= val;
        }
        for i in 0..n {
            current_sum[i+1] += current_sum[i];
        }
        for i in 0..n {
            dp[i] = current_sum[i] % MOD;
        }
    }
    println!("{}", dp[n-1]);
}