女，5岁，因发现心脏杂音4年来诊。查体于胸骨左缘2、3肋间可闻Ⅳ级粗糙SM，向上传导，可及震颤，P2减弱，心电图示右室肥厚。

本症超声心动图的典型改变是（）。

A.房水平左向右分流

B.室水平左向右分流

C.动脉水平左向右反流

D.主动脉内高速血流

E.肺动脉高速血流

Directions.

A. Study the following picture carefully and write an essay in no less than 160-200 words.

B. Your essay must be written clearly on ANSWER SHEET 2.

C. Your essay should meet the requirements below:

1) Interpret the following picture,

2) analyze possible reasons for this situation, and

3) suggest counter-measures.