#include <bits/stdc++.h>
#define IOS ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define i64 long long
#define endl '\n'
#define lb(x) ((x) & (-x))
using namespace std;
const i64 mod = 998244353;
const int maxn = 1e3+10;
i64 c[1005][1005];
signed main()
{
    IOS;
    for (int i = 0; i <= 1000; ++i)
    {
        for (int j = 0; j <= i; ++j)
        {
            if (!j) c[i][j] = 1;
            else c[i][j] = (c[i - 1][j] + c[i - 1][j - 1]) % mod;
        }
    }
    int t;
    cin >> t;
    while(t--)
    {
        int n,k,m;
        cin >> n >> k >> m;
        string a,b;
        cin >> a >> b;
        int cnt = 0;
        for(int i = 0; i < n; ++i) if(a[i] != b[i]) cnt++;
        vector<vector<i64>> dp(k+1,vector<i64> (n+1));
        dp[0][cnt] = 1;
        for(int i = 1; i <= k; ++i)
        {
            for(int j = 0; j <= n; ++j)
            {
                for(int l = 0; l <= j && l <= m; ++l)
                {
                    if(n-j >= m-l) dp[i][j - l + m - l] = (dp[i][j - l + m - l] + dp[i-1][j] * c[j][l] % mod * c[n-j][m-l] % mod) % mod;
                }
            }
        }
        cout << dp[k][0] << endl;
    }
    return 0;
}