---Has Jack finished painting the picture yet?

--- I’ve no idea. But he______ it the whole afternoon.

A．was painting

B．painted

C．had painted

D．have painted

患者，男，54岁，压榨性中心性胸痛发作后3小时就诊。查体：面色苍白，发汗。血压110/90mmHg，脉搏78次/分，心音正常。心电图示ST段抬高。实验室检查：钾3.2mmol/L，钠138mmol/L，尿素9.2mmol/L，CK90U/L。

如患者左胸痛发作是在8小时就诊，进行生化检查时应首选检查下列哪项指标

A．CK-MB

B．LD1

C．Mb

D．cTn

E．CK