PT 62 S4 Q22

Researchers have found that children in large families—particularly the ... ...

Which one of the following, if true, most supports the researchers' hypothesis?
(A) In countries where the average number of children per family has decreased over the last century, the incidence of allergies has increased.
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Complete Section: LR-B, Dec. '10 LSAT (PT 62 Sec. 4)