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: How long had the band Gary joined in 1964 been in existence when he did join it? Passage:Gary Pickford-Hopkins began his musical career at the age of 16 with a local Neath group called The Smokestacks in 1964. He soon joined Eyes Of Blue, who in 1966 won the Melody Maker's Battle of the Bands, they have recorded two albums, John Weathers was on drums and he would later follow Pickford-Hopkins to Wild Turkey and then join Gentle Giant. In 1970, he briefly joined Big Sleep, and a year later he went to play with Glenn Cornick's Wild Turkey which recorded three albums from 1971 to June 1974, when he joined Rick Wakeman's English Rock Ensemble to produce the live album Journey to the Centre of the Earth in 1974 which reached number one on the UK Albums Chart and peaked at number 3 on the Billboard 200 in the United States. It was certified gold in the United States and United Kingdom. He later sang on Wakeman's third solo album The Myths and Legends of King Arthur and the Knights of the Round Table. In 1976, he sang on an album from a band called The Good Times Roll Band with The Faces' bass player Tetsu Yamauchi, the album simply titled Tetsu & The Good Times Roll Band was recorded in 1976 but was published in 2009.
Links: a. Gentle Giant b. Phil Ryan (musician) c. Journey to the Centre of the Earth (album) d. UK Albums Chart
b