A series is given with one term missing. Select the correct alternative from the given ones that will complete the series.
-36, -68, -132, -260, ?, -1028, -2052, -4100

Given: -36, -68, -132, -260, ?, -1028, -2052, -4100

Logic: Double difference are doubling.

-68 − (−36) = −32

-132 − (−68) = −64
-260 − (−132) = −128

Differences are doubling:
−32, −64, −128, −256, −512, −1024, −2048

Next difference = −256

Missing term = -260 − 256 = −516

Check: -516 − 512 = −1028 (matches next term)

So, the missing term is -516.

Thus, correct option is (a).