In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.

Question: Which American composer who were pioneers in Minimal music was born first? Passage:Minimal music is a form of art music that employs limited or minimal musical materials. In the Western art music tradition, the American composers La Monte Young, Terry Riley, Steve Reich, and Philip Glass are credited with being among the first to develop compositional techniques that exploit a minimal approach. It originated in the New York Downtown scene of the 1960s and was initially viewed as a form of experimental music called the New York Hypnotic School. As an aesthetic, it is marked by a non-narrative, non-teleological, and non-representational conception of a work in progress, and represents a new approach to the activity of listening to music by focusing on the internal processes of the music, which lack goals or motion toward those goals. Prominent features of the technique include consonant harmony, hypnotic rhythmic pulses or steady drones, stasis or gradual transformation, and often reiteration of musical phrases or smaller units such as figures, motifs, and cells. It may include features such as additive process and phase shifting. Phase-shifting leads to what has been termed phase music. Minimal compositions that rely heavily on process techniques that follow strict rules are usually described as process music.
Links: a. Phrase (music) b. La Monte Young c. Drone (music) d. Cell (music)
b