左侧位心脏照片上，心后缘与食管前的间隙消失，提示（）

A.左房扩大

B.右房扩大

C.左室扩大

D.右室扩大

E.以上都不是

— Where is Toronto?

— ________.[ ]

A. It's in the United States

B. It's in Russia

C. It's in Canada

D. It's in Singapore