Brainliest and 20 points!!!!

Represent the geometric series using the explicit formula.

2, −8, 32, −128, …

f(n) = 2 ⋅ (−4)↑(n−1)
f(n) = 2 ⋅ (4)↑(n−1)
f(n) = f(n − 1) ⋅ (−4)
f(n) = f(n − 1) ⋅ (4)