四、閱讀測驗【請依照段落上下文意，選出最適當的答案】第一篇：Considering the amount of time that some people spend trying to improve their memories, it may come asa shock that, according to most researchers, at least as important as our ability to remember is our ability to forget.One important effect of our ability to forget is a clear conception of the passage of time-- vivid memories aretypically most recent, while faded memories are commonly products of much earlier experiences. A second vitalconsequence of forgetting is our ability to adapt to new situations. For example, a behavior that one learns as a child(“Don’t talk to strangers!”) may not be appropriate for a later period in life. Consider, for a moment, what life wouldbe without the capacity to forget: the brain would suffer from such a jumble of information that the simplest of dailytasks would become impossible to accomplish successfully.So how is it that humans forget? While scientists are not absolutely certain about the biological mechanism atwork, the most common theory assumes that the human brain has a limited amount of space for memory. Theysuggest two basic processes for forgetting. The first, retroactive forgetting, occurs when new memories take the placeof old ones. The second, called proactive forgetting, occurs when old memories are somehow stronger than new onesand thus overwhelm and erase them. However, in spite of the fact that humans are quite good at forgetting, thereare some scientists who insist that traces of memories are always left behind after they have apparently beenforgotten, a theory which has the advantage of accounting for the ability of subjects under hypnosis to recallsupposedly forgotten details of past experiences.Of course, not all forgetfulness is considered normal. Some types of forgetting result from illness or braintrauma and can range from profound amnesia -- total loss of memory -- to aphasia --loss of some functions of speech.
41. The passage mainly discusses _____.
(A) the benefits of forgetting
(B) methods for improving memory
(C) brain illnesses
(D) old and new memories