TOEFL Reading: ETS-TOEFL阅读机经 - 5T45LNI2H4A8P05YL$

Paragraph 5 states that swimming and flying are more efficient than walking because A. swimming and flying animals make tail strokes and wingbeats much less often than walking animals take steps B. swimming and flying animals use more muscles than walking animals do C. swimming and flying do not require as much acceleration and deceleration with every movement D. animals that are swimming or flying can accelerate and decelerate more quickly than can animals that are walking