On a coordinate plane, a step graph has horizontal segments that are each 1 unit long. The left end of each segment is a closed circle. The right end of each segment is an open circle. The left-most circle goes from (negative 3, 3) to (negative 2, 3). Each segment is one unit lower and 1 unit farther to the right than the previous segment. The right-most segment is just a closed circle at (3, negative 3). Which function and domain could represent the given graph?
f(x) = 1 – ⌊x⌋; –3 < x < 3
f(x) = 1 + ⌊x⌋; –3 ≤ x ≤ 3
f(x) = –⌊x⌋; –3 ≤ x ≤ 3
f(x) = ⌊x⌋; –3 < x < 3