To find the volume of the driveway, we need to multiply its length, width, and depth.
The length of the driveway is 90 feet, the width is 15 feet, and the depth is 4 feet.
Volume = length x width x depth
Volume = 90 ft x 15 ft x 4 ft
Volume = 5400 cubic feet
Therefore, 5400 cubic feet of concrete will be required to fill the driveway.
Hence, the correct answer is 5400 ft³.