Warming temperatures and changing rainfall patterns may reduce diet diversity（多样性）among children around the world and may even destroy efforts to improve food security.Researchers analyzed the results of health surveys from more than 107，000 children in 19 countries— in Asia；North,south-east and West Africa；as well as Central and South America.
In the surveys,the diversity of a child's diet was quantified（量化）based on their intake of foods from different food categories,including grains,milk products and meat.On average,3.2 food categories out of 10 were consumed by the children aged 5 and under,but the situation varied from country to country.Children in Colombia ate from 4.8 food categories on average,while those in Lesotho ate from just 1.8.
To study whether climate affected the diversity of the children's diets,the researchers linked the results from each country to 30 years of rainfall and temperature data in the surveyed areas.They found that long-term higher temperatures were associated with lower diet diversity for children everywhere except Central America.
There were also shorter-term trends.In North Africa and South America,there was typically a reduction in diet diversity in countries that experienced above-average temperatures the year before the survey.In Central America and West Africa,diets typically became more diverse in countries that experienced above-average rainfall in the previous year.In some countries,the researchers say that the negative effects of climate change on diet diversity was great,and that they may even destroy efforts to improve food security.
Diet diversity is a useful standard for areas with high rates of child malnutrition（营养不良），says Daniel Mason D'Croz,an Australian researcher. "Children need a fruit or a vegetable or animal product besides the rice— that's an important thing for people to know," he says.And he also added that recent follow-up studies have provided more authoritative evidence of the effect of climate change on reducing diet diversity.



Why did researchers study the data of rainfall and temperature in the surveyed areas？ ______

A. To learn the diversity of a child's diet from different countries.
B. To confirm the negative effects of climate on food production.
C. To explore the effects of climate on the children's diets diversity.
D. To link the rainfall and temperature data to lower food categories.

What does the underlined word "they" in Paragraph 4 refer to？ ______

A. The researchers.
B. Some countries.
C. The negative effects.
D. Above-average temperatures.

What can we infer from the last two paragraphs？ ______

A. Children need fruits or vegetables except the rice.
B. Reducing diet diversity may cause child malnutrition.
C. Higher temperatures will make the diet more diverse.
D. Above-average rainfall leads to reducing diet diversity.

What could be the best title for the text？ ______

A. Children's Diet Will Be Influenced by Rainfall
B. Food Security Varies from Country to Country
C. Climate May Affect the Diversity of Children's Diet
D. Scientists Are Making Efforts to Change Children's Diet