What is the 7th term of the geometric sequence 4, −20, 100, …? −312,500 −12,500 62,500 1,562,500?

The n-th term a[n] is given by
.. a[n] = 4*(-5)^(n -1)
Then
.. a[7] = 4*(-5)^6 = 62,500

The 3rd selection is appropriate.