for _ in range(int(input())):
    n, m = map(int, input().split())
    a = set(map(int, input().split()))
    b = set(map(int, input().split()))
    s = a.intersection(b)
    if len(s) != 0:
        print("YES")
        print(1, s.pop())
    else:
        print("NO")
