4. What of the following is/are TRUE about the use of reference letters/checks as a selection tool? (A) Research shows that reference checks are generally weak predictors of job performance (B) Reference checks generally yield positive information about an applicant (C) The validity of the reference check will be higher if it comes from someone who knows the applicant but is not on the list of references provided by the applicant (D) All of the above (E) Two of A, B, and C