The defining model for the career of a self-sustaining, trend-setting rock group of the 1960s, as set forth by the beach boys, included:

a) demonstrating a mastery of the basic early rock 'n' roll styles.
b) creating original material based on, and extending, those styles.
c) branching out totally beyond the traditional forms, sounds, and lyrical content of rock 'n' roll to create something truly different and unique.
d) both a and b
e) all of the above