May you me. do not skip this question. urgent!

C

Step-by-step explanation:

The common ratio can be < 0

All that means is the entry's signs alternate.

For example

r = - 2

a = 3

Series = 3    -6    18     -54 etc. The members of the series become larger and larger in magnitude and the series diverges. It is not clear where it might stop.

-1 < r < 0 gives a much better behaved result.

The point is that c is incorrect.