Answer:
A
Step-by-step explanation:
The explicit formula for a geometric sequence is
f(n) = f(1) [tex](r)^{n-1}[/tex]
where f(1) is the first term and r the common ratio
Here f(1) = 64 and r = [tex]\frac{f(2)}{f(1)}[/tex] = [tex]\frac{16}{64}[/tex] = [tex]\frac{1}{4}[/tex] , then
f(n) = 64 [tex](\frac{1}{4}) ^{n-1}[/tex] → A
