請依下文回答第 36 題至 40 題All whales fall into two groups, those with teeth and those without. Both beluga and dolphins belong to thesuborder of toothed whales known as Odontoceti, along with porpoises, narwhales, pilot whales, killer whales,and the largest toothed creature in the world, the sperm whale. Size differences among the Odontoceti areremarkable. A common porpoise will run only 4 or 5 feet in length and 300 pounds in weight; a sperm whalemay be 10 times as long and 300 times as heavy. The beluga falls in between, weighing up to 2,000 pounds.And it does chirp. In fact, it makes a great variety of squeaking, whistling, and clicking sounds, which haveearned it the name of sea canary. The toothless, or baleen, whales belong to the suborder of Mysticeti. This isa group of generally large whales, formerly abundant in all the oceans of the world. Though reduced byhunting, most species are still found along the coasts of the United States and Canada. All but two of theMysticeti reach 40 feet or more at maturity, with the blue whale running up to 100 feet and tipping the scalesat up to 130 tons. This whale is by far the largest creature that has ever lived on the Earth, 4 times the weightof the largest dinosaur, and 30 times that of an elephant.
【題組】36 With what topic is the passage mainly concerned?
(A) Breeding habits of whales
(B) Efforts to preserve whales
(C) The intelligence of whales
(D) Differences between whales