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