An SLP determines the mean length of utterance (MLU) of a language sample from a three-year-old child. Two weeks later, the SLP reevaluates the same sample and again determines the MLU. The extent to which the two scores are similar is most directly a function of the
(A) validity of the scores
(B) reliability of the scores
(C) skewness of the score distribution
(D) speededness of the measure