Nhận biết (M1)

Why do flat-headed cats purr but jaguars roar? Researchers hypothesize that this difference between the two feline species may be partly due to a U-shaped bone in their throats called the hyoid. Flat-headed cats, which are much smaller than jaguars, have a rigid hyoid that rumbles when the cat’s larynx vibrates, resulting in a purr. By contrast, jaguars have a somewhat flexible hyoid, and the bone is attached to the skull with a stretchy ligament that flat-headed cats lack. These traits allow jaguars and most other species of big cats to produce powerful roars. The same traits may also prevent most big cats from purring.

According to the text, which trait do researchers think may contribute to a flat-headed cat’s ability to purr?

• A.

  The shape of the flat-headed cat’s larynx

• B.

  The ligament attaching the hyoid bone to the flat-headed cat’s skull

• C.

  The flat-headed cat’s rigid hyoid bone

• D.

  The relative size of the flat-headed cat’s body and throat