Option 1: At x = 0,
f(x) = 128(0.5)^0 = 128(1) = 128 (not satisfy the ordered pair which is (0,128))
Option 2: At x = 1,
f(x) = 128(0.5)^1 = 128(0.5) = 256 (not satisfy the ordered pair which is (1,256))
Option 3: At x = 3,
f(x) = 128(0.5)^3 = 128(1/2)^3 = 128(1/8) = 16 (satisfy)
Hence, the answer is Option 3.