Schoenberg had four compositional phases during his career.
A) true

B) false

B) false

Explanation:

Schoenberg did not have just four compositional phases during his career, rather, he had  8 additional phases, making it 12, a Twelve-tone period. Schoenberg's serial method of composition with twelve notes grew to one of the most central and polemical issues amidst American and European musicians throughout the mid-to late-twentieth century. Therefore, the statement is false, and the answer is false.

the answer is b. i'm positive it's that answer.