What are the explicit equation and domain for an arithmetic sequence with a first term of 7 and a second term of 3? A. an = 7 − 4(n − 1); all integers where n ≥ 1 B. an = 7 − 4(n − 1); all integers where n ≥ 0 C. an = 7 − 3(n − 1); all integers where n ≥ 1 D. an = 5 − 3(n − 1); all integers where n ≥ 0