試題詳解

49. Although scientists know very little about giraffes, they do know that giraffes are in trouble. Habitat loss and poaching have reduced their numbers by an estimated 40 percent in the last 30 years.____________. To combat this decline, Dr. Brown and other scientists have been surveying and monitoring as many wild giraffe populations as they can.
Which of the followings is the most appropriate supporting sentence of this paragraph?
(A) Giraffes don't need much sleep to function.
(B) Some subspecies are now critically endangered.
(C) Surveying and monitoring giraffes is very challenging.
(D) This reduction has led to a new discovery about giraffes.