The step function f(x) is graphed. On a coordinate plane, a step graph has horizontal segments that are each 2 units long. The left end of each segment is a closed circle. The right end of each segment is an open circle. The left-most segment goes from (negative 3, negative 3) to (negative 1, negative 3). Each segment is 2 units higher and 2 units farther to the right than the previous segment. The right-most segment goes from (3, 3) to (5, 3). What is the value of f(−1)?
a.)-3
b.) -1
c.) 0
d.) 1