题目内容：

    Researchers in Singapore found that eating mushrooms over twice per week could help prevent memory and language problems later in life.

According to the study, published in The Journal of Alzheimer's Disease, there is a unique antioxidant (抗氧化物质) present in mushrooms that helps protect certain brain functions.

Researchers observed 663 Chinese adults aged over 60 whose diets and lifestyles were tracked from 2011 to 2017. In the study, the participants were asked how often they ate six different types of mushrooms: oyster, shiitake, white button, dried, golden and tinned. The findings showed that eating more than two shares of mushrooms per week somehow lowered the chances of mild cognitive impairment (MCI) by 50% against those who ate fewer than one share.

MCI is a condition that can make people forgetful, affect their memory and cause problems with language, attention and finding the exact position of objects in space. Changes in behavior can be not very noticeable and not serious enough to be known as dementia (痴呆).

Participants who ate more mushrooms were found to perform better in thinking and processing exams and also exhibited a faster processing speed. The advantage was reportedly more apparent in those who ate more than two shares a week or more than 300 grams.

The scientists pointed out, however, that they have yet to put up a direct link between the fungi(蘑菇) and brain function.

The researchers also acknowledged that since this study mainly relied on self-reported information on mushroom intake and other dietary factors, further studies may be required. Still, the lead study author Lei Feng is encouraged by their findings. ''This relevance is surprising and encouraging, '' Lei said.

Mushrooms are one of the richest dietary sources of ergothioneine (麦角硫茵氨基酸) — a substance which we humans can’t make on our own.

1.What aspect of research did researchers mainly do in paragraph 3?

A.Culture of diets. B.Existence of MCI.

C.The types of mushrooms. D.The benefit of eating mushrooms.

2.What can we know about MCI?

A.It can affect memory seriously.

B.It can result in language problems.

C.It can make people easy to be lost.

D.It can reduce the chance of forgetfulness.

3.What is the result if students often eat more mushrooms?

A.They love communicating with others.

B.Their thinking ability is quicker than the majority.

C.Their processing speed will be faster.

D.Their academic performance improves significantly.

4.Where is this passage most likely from?

A.A science report. B.An advertisement.

C.Adult’s literature. D.Scientific fiction.