单选题 If remote-controlled cars are more expensive than mechanical cars, and radio-controlled cars are more expensive than remote-controlled cars, which of the following statements must be true?

A、 Mechanical cars are the most expensive.
B、 Radio-controlled cars are the most expensive.
C、 Radio-controlled cars are cheaper than remote-controlled cars.
D、 Mechanical cars are more expensive than remote-controlled cars.

【正确答案】 B

【答案解析】遥控车比机械车贵，无线电遥控车又比遥控车贵，因此可推知无线电遥控车是最贵的。