MAP3.0的协议结构中，局域网的MAC协议选用（）网络服务。

A.802.3协议，网络层选用面向连接型

B.802.4协议，网络层选用面向连接层

C.802.3协议，网络层选用无连接型

D.802.4协议，网络层选用无连接型

Sometimes we have specific problems with our mother; sometimes, life with her can just be hard work. If there are difficulties in your (1) , it’s best to deal with them, (2) remember that any (3) should be done (4) person or by letter. The telephone is not a good (5) because it is too easy (6) either side to (7) the conversation.

Explain to her (8) you find difficult in your relationship and then (9) some new arrangements that you think would establish a (10) balance between you. Sometimes we hold (11) from establishing such boundaries because we are afraid that doing (12) implies we are (13) her. We need to remember that being (14) from our mother does not (15) mean that we no longer love her. If the conflict is (16) and you cannot find a way to (17) it, you might decide to give up your relationship with your mother for a while. Some of my patients had (18) "trial separations". The (19) allowed things to simmer down, enabling (20) .

（13）（）

A.mustering

B.ejecting

C.insulting

D.retaliating