1
2 2
1 1
1 2
 1
1 3
3
1 2 3
 1
1 1
1000
1000
 1
2 2
2 2
2 2
 5
4 5
10 8 6 4
1 2 3 4 5
1 1
3
3
1 1
3
2
5 3
1000 2 2 2 3
3 1 5
5 5
1 2 3 4 5
1 2 3 4 5
 1
4 4
1 1 1 1
1 2 3 4
 1
2 3
1 1
1 2 3

YES
1 1
 YES
1 3
 YES
1 1000
 YES
1 2
 YES
1 4
YES
1 3
NO
YES
1 3
YES
1 1
 YES
1 1
 YES
1 1



import java.util.*;

public class ques1 {
    public static String solution(HashSet<Integer> hs,int[] B,int M){
        for(int i =0;i<M;i++){
            if(hs.contains(B[i])){
                return "YES"+":"+B[i];
            }

        }
        return "NO";
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int T = sc.nextInt();
        for(int t =0;t<T;t++) {
            int N = sc.nextInt();
            HashSet<Integer> hs = new HashSet<>();
            int M = sc.nextInt();
            int[] B = new int[M];
            for(int i=0;i<N;i++) hs.add(sc.nextInt());
            for(int j=0;j<M;j++) B[j]=sc.nextInt();

            String str = solution(hs,B,M);
            if(str.equals("NO")){
                System.out.println("NO");
            }else {
                String a = str.split(":")[1];
                System.out.println("YES");
                System.out.println(a);
            }
        }
    }
}
