t=int(input())
for _ in range(t):
    n,m=map(int,input().split())
    a=list(map(int,input().split()))
    b=list(map(int,input().split()))
    a=set(a)
    b=set(b)
    flag=0
    for i in a:
        if(i in b):
            print("YES")
            print(1,i)
            flag=1
            break
    if(flag==0):
        print("NO")
