三、閱讀測驗:下列選文後有五個問題。請仔細看完選文後,從每題的A、 B、C、D 四個選項中,選出最適當的答案。(10 分) One key to the stability of natural systems is the diversity of plants, insects,
and animals that live in them. If nature is left undisturbed by humans, it naturally
evolves ecosystems with incredible diversity, leading to many inter-connected
negative feedback loops that suppress disruptive changes. Recent research shows
that diverse plant ecosystems are not only more resilient and robust, they’re also
more productive and consume more CO2. On the other hand, when humans
manage an ecosystem to maximize output, they typically create a monoculture just one crop with as few weeds and insects as possible. In the short run, a
simplified ecosystem gives humans rich returns of that one crop. But it’s also
very vulnerable. Because any single crop falls easily to unexpected loss, farmers
should plant diverse crops and rotate them on their fields. The researchers
studying productivity from biodiversity have found that polycultures of about ten
species produced the greatest bioproduct.
【題組】5. Which of the following is true according to this passage?
(A) The more diverse a natural system is, the more stable.
(B) Maximum output of a single crop may be harmful to the whole system.
(C) Human intervention in a natural system is often counterproductive.
(D) All of the above