请选择DCBA/C0I:R8j5W+C0k)\ Neither Mary nor her brother _________ good at singing.(c6_6z3U0r*^6Z;_;K
A.is(c6_6z3U0r*^6Z;_;K
B.are(c6_6z3U0r*^6Z;_;K
C.is not(c6_6z3U0r*^6Z;_;K
D.are not(c6_6z3U0r*^6Z;_;K