What was a significant turning point in Takahiro Sakurai's voice acting career?

A. When he sang his first character song in the movie Gate Keepers
B. When he joined 81 Produce
C. When he got regular roles in two TV anime in a row, Digimon Adventure and Sensual Phrase, in 1999
D. When he landed a role in a radio drama during his time at the training school
Answer: 