—Where are Jim and Tom? Their mother is looking for them.

—They _____ over there.  

A. run          B. runs         C. are running 

关于黄素囊肿的说法，正确的是：①多与滋养细胞肿瘤伴发；②多呈单房；③多为双侧性；④其大小常不超过4cm（）

A.①②③

B.①③

C.②④

D.④

E.①②③④