The answer is both B and C
positive chromic acid test is indicated by disappearance of orange colour from chromic ions and appearance of blue-green color from Chromium (iii) ion (reduction of chromium ion from CrO4 - to Cr3+)
positive chromic test indicated functional groups that can be oxidized.
cyclohexanol can be oxidized to become cyclohexanone
and pentan-3-ol can be oxidized to become pentan-3-one
hence both B and C will show positive chromic acid test
A) tert butanol although contains alcohol functional group, cannot be further oxidized as it is a tertiary alcohol