When a single dropped coffee filter (or a stack of coffee filters) has reached terminal velocity?

is it one or more than one of the answer:





A greater net force acts on a stack of four filters than on a single filter?


A greater downward force acts on a stack of four filters than on a single filter?


A greater upward force acts on a stack of four filters than on a single filter?

When a single dropped coffee filter (or a stack of coffee filters) has reached terminal velocity?
The terminal velocity is constant: then a = 0 and net force = 0.