What do I do pls I don’t know it’s a number trick htw

The first term of a sequence is -12. the recursive formula for the sequence is an = an-1 + 9. what are the next 3 terms in the sequence? a) -3, -15, -27 b) -3, 6, 15 c) -3, -6, -3 d) -3, -6, 3