1. His technique in composition is the use of semi-tone scale. a. Cage
b. Debussy
c. Glass
d. Schoenberg

Schoenberg

Explanation:

The twelve-tone technique—also known as dodecaphony, twelve-tone serialism, and (in British usage) twelve-note composition—is a method of musical composition first devised by Austrian composer Josef Matthias Hauer,[not verified in body] who published his "law of the twelve tones" in 1919.

answer; (binary). i believe this is the correct answer;