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()))
	flag=0
	for i in a:
		for j in b:
			if(i==j):
				flag=1
				print("YES")
				print(1,i)
				break
		if(flag):
			break
	if(flag==0):
		print("NO")