男性，56岁，心悸、胸闷2个月，突发胸痛2小时，呈持续性疼痛，伴呼吸困难，服用各种药物不能缓解。查体：心率85次／分，心音低，心律不齐，可未闻及期前收缩。

该患者最有可能的诊断是（）。

A.心肌梗死

B.心肌病

C.气胸

D.心包积液

E.心房纤颤

The Value Line index is an equally weighted geometric average of the return of about 1700 firms. What is the value of an index based on the geometric average returns of three stocks, where the returns on the three stocks during a given period were 20% , -10%, and 5% 9（）

A. 4.3%.

B. 5.0%.

C. 11.7%.