Final answer:
B) 1960. Arthur Ashe won the U.S. Junior Indoor singles titles in 1960.
Step-by-step explanation:
The correct answer is B) 1960.
Arthur Ashe won the U.S. Junior Indoor singles title in 1960, making him the first African American to win the tournament. This victory was significant not only for Ashe but also for the sport of tennis, as it challenged racially discriminatory practices in the sport.