(A) The argument is concerned only with whether a bias toward personally acquainted applicants is present or absent; it is not concerned with whether such a bias may, in fact, lead to placements that are more successful in the long term.

(B) CORRECT. For the argument to establish lack of bias toward certain applicants, the proportion of "previously acquainted" people among those applicants chosen for placement must reflect the corresponding proportion among all applicants. In other words, if eight out of the ten parents actually chosen were personally acquainted with the staff, then a similar majority of all applicants should have been similarly acquainted with the staff. Alternatively, use the negation test. If this statement is false, then the majority of qualified applicants were in fact unacquainted with agency staff – a situation in which the placement of eight of ten babies with personally acquainted applicants is a clear signal of bias. Since the negation of this statement defeats the argument, the original statement must be assumed.

(C) The argument is concerned only with determining whether a bias is demonstrated by the agency's ten most recent placements; it does not involve the idea of whether those placements were made at a typical rate.

(D) Applicants who do not meet the criteria are irrelevant; the argument is concerned with determining whether a bias exists among fully qualified applicants. Therefore, the relative proportion of unqualified candidates among all applicants does not affect the argument.

(E) Although all ten of the agency's most recent placements may indeed have been placed with parents who "far surpassed" the criteria, there is nothing in the argument to suggest that all successful applicants must substantially surpass those criteria (as opposed to simply meeting or fulfilling them).