Task: Question Answering
Input (English): Question: In the arithmetic sequence t1, t2, t3, ..., tn, t1=23 and tn= tn-1 - 3 for each n > 1. What is the value of n when tn = 8?

 Option A: -1

 Option B: 6

 Option C: 10

 Option D: 14

 Option E: 20
Output (English): Option B