Read the following excerpt from Alexander Pope's "Essay on Criticism" and determine the rhyme scheme he is using.

"'Tis hard to say, if greater want of skill Appear in writing or in judging ill; But, of the two, less dang'rous is th' offence To tire our patience, than mislead our sense. Some few in that, but numbers err in this, Ten censure wrong for one who writes amiss; A fool might once himself alone expose, Now one in verse makes many more in prose."

a. ABAB CDCD
b. AB AB CD CD
c. AA BB CC DD
d. AA BC BC DD