Researchers believe that if mothers are exposed to more pesticides in the first few months of pregnancy, the babies born may be less intelligent. They believe that the embryonic brain begins to develop shortly after pregnancy, so the pre-pregnancy is the baby's brain In the critical period of development, exposure to more pesticides may change the environment around the developing embryo's brain in pregnant women. Which of the following, if true, would best support a researcher's point of view? ["Many babies are born early due to their mothers' exposure to pesticides.", "Insecticides are a potential threat to people's health, and it can also cause many diseases such as Parkinson's disease, cancer and mental illness.", 'Previous research has found that increased exposure to pesticides can cause thyroid problems in pregnant women, and the thyroid status of pregnant women can affect the intellectual development of the fetus.', 'Researchers conducted a follow-up survey of 1,500 pregnant women and found that children born to pregnant women who were more exposed to pesticides performed significantly worse in mathematics and language.']