___________ impolite ___________ at anyone with your chopsticks.
A:That's; to point
B:That's; to pointing
C:It's; to point
D:It's; to pointing
食物的消化与吸收是靠消化系统来完成的.如图是组成人体消化系统的部分消化器官.下列叙述错误的一项是( )