ACCORDING TO THE PASSAGE, WHICH STATEMENT IS TRUE

4. According to the passage, which statement is true?

A. Keyhole surgery cannot be used in major operations.

B. Keyhole surgeons have to keep straight backs and should not enjoy plenty of elbow room.

C. The smallest robots have long been exploited in endoscopic surgery.

D. The viewing technology that endoscopic doctors are making use of has been borrowed from the

aerospace industry.