Correct Answer - Option 2 : 15
Arun position in a class = 17th
Total number of students in the class = 31
Total number of students in the class = Arun position from the top + Arun position from the bottom - 1
Arun position from the bottom = Total number of students in the class - Arun position from the top + 1
= 31 - 17 + 1
= 14 + 1
= 15
Hence, the correct answer is "15".