It was in the lab was taken charge of by Johnson they did the experiment.
A. where；which
B. which；that
C. which；which
D. that；which
网友回答
A. where；which
(答案→)B. which；that
C. which；which
D. that；which
解析：考查复杂句：第一空是定语从句先行词是the lab，定语从句中缺少主语，用that或which引导定语从句，第二空是强调句，强调的是in the lab，句意：就是在Johnson负责的实验室，他们做实验的。选B。