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 common_member(a, b): 
	a_set = set(a) 
	b_set = set(b) 

	if (a_set & b_set): 
		return list(a_set & b_set) 
	else: 
		return None

t = int(input())
for t1 in range(t):
	m,n = [int(n1) for n1 in input().split()]
	a = [int(n1) for n1 in input().split()]
	b = [int(n1) for n1 in input().split()]
	c = common_member(a,b)
	if c!=None:
		print('YES')
		print(c[0])
	else:
		print('NO')