When the technique know as organ transplant was introduced in the early 1960s, it was feared that grafts from nonhuman animals might creat "Ebola," a new virus never before found in humans that might spread from people to people and it would kill vast numbers of humans who would have no natural defences against it.
(A)it would kill vast numbers of humans who would have no natural defences against it
(B)it would kill vast numbers of humans with no natural defences against it
(C)kill vast numbers of humans who would have no natural defences against it
(D)kill vast numbers of humans who have no natural defences against it
(E)kill vast numbers of humans with no natural defences against them
答案是C
請問為什麼這裡要用would have no natural defences 不能用have no natural defences (如D)?
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