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

t=int(raw_input())
for i in range(t):
     n,m=map(int,raw_input().split())
     a=[int(i) for i in raw_input().split()]
     b=[int(i) for i in raw_input().split()]
     if n<=m:
          for j in range(len(a)):
               if a[j] in b:
                    print 'YES'
                    print a[j]
                    break
          else:
               print 'NO'
     else:
          for j in range(len(b)):
               if b[j] in a:
                    print 'YES'
                    print b[j]
                    break
          else:
               print 'NO'