Did Grandma seem forgetful at the holiday parties last month？ It could be time to put her

on a diet. Sharply【C1】______calories(卡路里)improves memory in older adults,according to a new study.

Research on the benefits of an extremely low-calorie diet【C2】______back to the 1930s, when scientists found that rats lived【C3】______to twice as long when they ate less than control animals. And how about in human？ To fill that【C4】______, scientist Agnes and her colleagues at the University of Muenster【C5】______50 healthy elderly subjects. The【C6】______volunteer was 60 years old and overweight. The researchers【C7】______assigned the volunteers to one of three groups. Twenty people were instructed to reduce their daily calorie【C8】______by 30%, while still eating a【C9】______diet. Another 20 were told to keep their calorie intake the same but increase their【C10】______of unsaturated(不饱和的 )fatty acids. The【C11】______10 volunteers did not change their diets.

After 3 months, all of the volunteers【C12】______a memory test in which they were shown 15 words and asked how many they could remember after 30 minutes.【C13】______average,those in the calorie-restriction group showed a 20%【C14】______over their baseline memory scores taken before they started their diets. Subjects in the other two groups showed【C15】______or no improvement. "Our study【C16】______provides some of the first【C17】______on the impact of calorie restriction on memory in the elderly, but this study has to be【C18】______up now," Floel noted. Her team plans to【C19】______larger studies to determine exactly【C20】______calorie restriction enhances memory.

【C1】

A．reducing

B．declining

C．burning

D．increasing