새끼 누를 죽이지 않은 암사자

[1~4] 다음 글을 읽고 물음에 답하시오.
For most of the year, it’s very quiet on the plains of the Serengeti. It’s only when the rains fall and the grasses appear (A) [what / that] paradise starts to get a little crowded. The vanguard of the most famous land migration in the world starts the long march south. The herds consist of mostly wildebeest. As the herds turn south for the final push, the heavens release ⓐtheir stores. Joining the wildebeest on the march (B) [is / are] zebra and Thomson’s gazelles. The gold at the end of the rainbow glistens. Once the grasses start growing, the ①extraordinary mass of grazers will settle for a short while. Each heavily pregnant cow, by some primal instinctive compulsion, will give birth to their offspring at the end of their long journeys. It’s the following two to three weeks that the predators have been waiting for, potential prey all delivered in their thousands. Back at the herds, there’s a spy in the grass. The lioness is at the center of literally thousands of newborn calves. A mother is forced to ②leave her minutes-old offspring. She makes a brave and final attempt to scare off this big cat. But her calf is now at another’s mercy. Why the lioness hesitates to (C) [make / making] the kill is unknown. Astonishingly, the calf is imprinting, compelled to treat a nearby warm body as its provider and protector, a very rare and usually ③fatal mistake. For some mysterious reason, the lioness ④tolerates the behavior. When the lioness’s attention is diverted to other preys, the calf is left alone. Somewhere in there is a mother bereft of her calf. It’s believed that mothers recognize their own calves by scent. But successful reunions here are ⑤common.
*Serengeti(세렝게티): 많은 초식동물과 조류들이 사는 탄자니아 서부에서 케냐 남서부에 걸쳐 있는 땅