Dr Thigpen Continued to Use His Original Scale to Measure

Multiple Choice

Dr. Thigpen continued to use his original scale to measure his patients' weights even though it no longer gave an accurate reading. Despite its inaccuracy, the scale did consistently give the same wrong weight each time a patient stepped on it. In this case, his scale lacks:

A) sensitivity.
B) reliability.
C) validity.
D) sensitivity, reliability, and validity.