Moji listed the solids in order of hardness as graphite < chalk < quartz. His peer group suggested some experimental errors that may have caused this to
happen. Which experimental error most likely led Moji to this conclusion?
A. Moji might have used color as an indication of hardness.
B. Moji might have thought that crumbliness was a sign of softness.
C. Moji might have thought that crumbliness was a sign of hardness.
D. Moji could have chosen hardness tests that were not reliable.