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 sol(lis1,lis2):
	s1 = set(lis1)
	s2 = set(lis2)
	p = s1.intersection(s2)
	if len(p) == 0:
		print('NO')
		return
	print('YES')
	print(1,end=' ')
	for i in p:
		print(i)
		break


k = int(input())
for i in range(k):
	n,m = list(map(int,input().split(' ')))
	lis1 = list(map(int,input().split(' ')))
	lis2 = list(map(int,input().split(' ')))
	sol(lis1,lis2)