—Are Jack and Mary your friends?     

—________.    [ ]

A. Yes, they are

B. They are    

C. No, they not

D. They aren’t

反映前侧壁心肌梗塞的心电图导联是（）

A.V₃、V₄、V₅

B.Ⅰ、aVL

C.Ⅱ、Ⅲ、aVF

D.Ⅰ、aVL、V₄、V₅

E.V₁、V₂、V₃