— It’s getting dark, but Mr. Chen is till at his office.

— No surprise. Who else can _______ he does.

A．do less work than

B．work as hardly as

C．work as hard as

D．be working hardly like

在传染病感染过程中最常见的是（）

A.隐性感染者

B.潜伏期携带者

C.慢性携带者

D.潜伏性感染者

E.显性感染者