Usually, Betty in colorful T-shirt in summer Awears B is dressed C is wearing D dresses

Usually, Betty in colorful T-shirt in summer Awears B is dressed C is wearing D dresses

b
idm 习语) (be) dressed in sth wearing sth 穿某物: The bride was dressed in white. 新娘穿一身白色的礼服.

be in general wear名词
(服装等)时髦的; 流行的; 时兴的
in wear名词
(经常)穿着; 时髦

选项D错的原因
是dress 一般用于被动语态【问题中用被动语态一人为主语，应是】
sb (be) dressed in sth wearing sth 穿某物:
The bride was dressed in white. 新娘穿一身白色的礼服.

dress (sb) up (in sth/as sb/sth) put on fancy dress, etc 化装打扮: Children love dressing up. 孩子们都喜欢化装打扮.
* dress (up) as a fairy, bandit, pirate, etc 打扮成仙女、 匪徒、 海盗等
* They were dressed up in Victorian clothes. 他们化装成维多利亚时代的人.

dress sth up (fig 比喻) make sth seem better or different by careful presentation 修饰; 掩饰:
The facts are quite clear; it's no use trying to dress them up. 事实很清楚, 想掩饰是没有用的.
* rumours dressed up as hard news 以假乱真的谣言.

B is dressed be dressed in为固定搭配，wear没这种用法

B