Lucy is the of the twins and she is the girl in her class.A. younger; youngerB. youngest;

问题补充：

Lucy is the of the twins, and she is the girl in her class.

A. younger; younger

B. youngest; youngest

C. younger; youngest

D. youngest; younger

答案：

A. younger; younger

B. youngest; youngest

(答案→)C. younger; youngest

D. youngest; younger

解析：英语中在两个中进行比较用比较级，在三个及以上进行比较用最高级。跟据前文在双胞胎中，可知前文用比较级。下文在班内进行比较用最高级。故选C。