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

def func():
	gg = [int(i) for i in input().split()]
	n = gg[0]
	m = gg[1]

	a1 = [int(i) for i in input().split()]
	a2 = [int(i) for i in input().split()]

	m1 = [0]*1005
	m2 = [0]*1005

	for i in a1:
		m1[i] += 1

	for i in a2:
		m2[i] += 1

	flag = 0

	for i in range(1005):
		if (m1[i] >0 and m2[i]>0):
			print ("YES")
			print (i)
			flag = 1
			break

	
	if (flag == 0):
		print ("NO")

t = int(input())

for i in range(t):
	func()



