It has to be said it was rather___________of him to ask a comple

It has to be said it was rather___________of him to ask a complete stranger to look after his luggage.
A、clever
B、ingenuous
C、conscientious
D、considerate
【正确答案】：B
【题目解析】：原句的意思是“据说他让一个陌生人来照看他的行李简直太天真了。”因此我们选择B. ingenuous（坦率的、天真无邪的、朴实的）。