题目内容：

    Babies’main food is rice cereal. But it is often poisoned. Studies have found that many brands contain measurable amounts of inorganic arsenic(无机砷),the most poisonous kind. It's not just nice: an August 2018 study tested 50 foods made for babies. including organic and nonorganic brands such as Gerber, Earths Best, and other popular labels, and found evidence of at least one dangerous heavy metal in every product. Fifteen of the 50 contained enough contaminants(污染物)to pose potential health risks to a child eating one serving or less a day.

Heavy metals can damage cognitive(认知的 )development in children, who are especially at risk because of their smaller size. Inorganic arsenic in drinking water has been found to lower the IQ scores of children by five to six ills. And as heavy metals accumulate in the body over time. they can raise the risk of cancer, diabetes and other physical conditions. Of course, finding you’re your favorite brand is contaminated is not a reason to panic. Low levels of exposure for short periods are unlikely to cause serious effects, but parents should focus on reducing the overall levels of these poisonous substances in their children's total diet to limit harm.

Heavy metals occur naturally on Earth and are present in soil and water. But pesticides(杀虫剂), mining and pollution increase their concentrations, and farming and food manufacturing processes can contribute even more.

Food makers are clearly of keeping baby food poison-free: roughly a third of the tested products did not contain worrisome metal levels. Some companies are already trying to look into the sources of contamination in their products and try to reduce them. More companies should follow. But the best chance of real change will come with laws. Currently there are no U. S rules on acceptable levels of heavy metals in baby foods.

The government and the food industry should unite to deal with the serious threat to our children.

1.What did the August 2018 study find?

A. Fifteen of the 50 food brands contained contaminants

B. All organic food brands contained some inorganic arsenic.

C. Earth’s Best proved to be a poison-free baby food brand.

D. All tested products were contaminated with heavy metals.

2.According to the second paragraph, inorganic arsenic in drinking water has a bad effect on children's_____

A. intelligence    B. behavior    C. sight    D. emotion

3.In the fourth paragraph, the writer indicates that_____

A. food storage is a major source of metal contamination in the food products

B. many food makers haven't taken enough safety steps to reduce metal levels

C. food makers should figure out the sources of contamination in their products

D. food companies must be banned from producing foods containing heavy metals

4.According to the writer, which of the following is the vital step to make a real difference to the worrying situation?

A. Stepping up baby food tests.    B. Listing harmful heavy metals

C. Making out relevant regulations    D. Punishing food law breakers.