26. What do medical experts say about bugs that jump species and infect humans?
(A) Air travel spreads viruses that come from animals.
(B) More viruses will appear in the future.
(C) All infections are caused by the African monkey.
(D) It’s impossible to find a cure for them.
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統計: A(5), B(19), C(1), D(2), E(0) #3473948
統計: A(5), B(19), C(1), D(2), E(0) #3473948