题目内容：

People with mentally taxing jobs, including lawyers and graphic designers, may end up having better memory in old age, research suggests.

A study of more than 1,000 Scottish 70-year-olds found that those who had had complex jobs scored better on memory and thinking tests.

One theory is that a more stimulating environment helps build up a “cognitive reserve” to help buffer the brain against age-related decline. The research was reported in Neurology.

The team, from Heriot-Watt University, in Edinburgh, is now planning more work to look at how lifestyle and work interact to affect memory loss. Those taking part in the study took tests designed to assess memory, processing speed and general thinking ability, as well as filling in a questionnaire about their working life.

The analysis showed that those whose jobs had required complex skills in dealing with data or people, such as management and teaching, had better scores on memory and thinking tests than those who had done less mentally intense jobs such as factory workers, bookbinders, or carpet layers.

While the study did not look at biological reasons for the protective effect of certain jobs, potential explanations include that structural changes within the brain mean less damage is accumulated over time.

Study leader Dr Alan Gow said: “Our findings have helped to identify the kinds of job demands that preserve memory and thinking later on.” “However,” He added, “while it is true that people who have higher cognitive abilities are more likely to get more complex jobs, there still seems to be a small advantage gained from these complex jobs for later thinking skills.”

Dr Simon Ridley, head of research at Alzheimer’s Research UK, said the study added to the growing evidence about factors that affected brain health as we aged.

“Keeping the brain active throughout life could be helpful and different types of work may play a role. However, it’s important to note that this study points to a small and subtle association between occupation and later-life cognition rather than offering proof that people’s occupation has a direct influence.”

1. According to the research, who may have the best memory in old age?

A. Taxi drivers.            B. Computer programmers.

C. Supermarket cashiers.    D. Motor mechanics.

2. Which of the following about the research work is TRUE?

A. The research team studied both environmental and biological factors.

B. The researchers filled in a questionnaire about their working life.

C. The research objects included people from various jobs and of different ages.

D. The research is helpful to the study of brain health and is still under way.

3. What Dr Alan Gow said implies that __________.

A. their findings are helpful to identifying the kinds of job demands

B. people who do more complex jobs may benefit later thinking skills greatly

C. there exist links between job demands and preservation of memory

D. he didn’t confirm the links between complex jobs and later thinking skills

4.We can learn from Dr Simon Ridley that __________.

A. different occupations may make a difference in keeping the brain active

B. people’s occupation has a direct influence on later-life cognition

C. the study added more evidence about the factors affecting aging

D. the study denied the association between jobs and later-life memory

5. What is the best title of the passage？

A. Aging affects brain health

B. Complex jobs may protect memory

C. Occupations influence aging

D. Complex jobs demand complex skills