问题补充：
Professor Smith is now the company, which was once Professor White.
A. in charge of; in charge of
B. in charge of; in the charge of
C. in the charge of; in the charge of
D. in the charge of; in charge of
答案：
A. in charge of; in charge of
(答案→)B. in charge of; in the charge of
C. in the charge of; in the charge of
D. in the charge of; in charge of
解析：考查固定搭配。固定搭配in charge of sth负责某事；in the charge of sb由某人负责；经验：斯密斯教授现在负责这家公司，这家公司曾经是有怀特教授负责的。故B正确。
