If for some number a and d, if first term is 1 a, second term is 1/(a+d), thrid term is 1/(a+2d) and so on, then 5th term of the sequence is?

If for some number a and d, if first term is 1 a, second term is 1/(a+

1.	If for some number a and d, if first term is 1 a, second term is 1/(a+d), thrid term is 1/(a+2d) and so on, then 5th term of the sequence is?
A.	a+4d
B.	a-4d
C.	1/(a+4d)
D.	none of the mentioned
Answer» D. none of the mentioned