Answer:
Teratogens.
Step-by-step explanation:
A teratogen is an agent that disturbs, during pregnancy, the development of the fetus or the embryo. Given that, in the exercise, the doctor suggests that the problem may have been a prenatal exposure, the best guess is a teratogen, which might include any maternal infections, drugs, chemicals or, in rare cases, even radiation. There are many things a teratogen might cause in later stages, such as Jill's problems of learning disability.