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


p=int(input())
print(p)
while(p>0):
    n,m=map(int, input().strip().split())
    l1=list(map(int, input().strip().split()))
    l2=list(map(int, input().strip().split()))
    t=False
    if n<m:
        for i in l1:
            if i in l2:
                print("YES")
                t=True
                print(1,i)
                break
    else:
        for i in l2:
            if i in l1:
                print("YES")
                t=True
                print(1,i)
                break
    if not(t):
        print("NO")
            
    p-=1