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

import sys
INP = lambda: sys.stdin.readline().strip()
INT = lambda: int(INP())
MAP = lambda: map(int, INP().split())
ARR = lambda: [int(i) for i in INP().split()]
def JOIN(arr, x=' '): return x.join([str(i) for i in arr])
def EXIT(x='NO'): print(x); exit()

for _ in range(INT()):
    n,m = MAP()
    arr = ARR()
    brr = ARR()
    c = {}
    if n>m: arr,brr = brr,arr
    for i in arr: c[i] = 0
    for i in brr:
        if i in c:
            print('YES')
            print(i)
            break
    else:
        print('NO')