The explicit formula for the nth term of an arithmetic sequence is an = a1 + (n - 1) • d. What is the simple formula corresponding to the explicit formula if the first term of the sequence is -10 and the difference between terms in the sequence is 3?
A. 3n - 13
B. 3n + 13
C. 3n - 7
D. 3n - 10
E. 3n + 10