He was only in__ at the time.
A. his 20's
B. the 20's
C. his twenties
D. the twenties
The two great men wrote those letters in__ .
A. 1870's
B. 1879s
C. the 1870's
D. the 1870
He came out__ in the track events.
A. first
B. one
C. the first
D. the one