While on final approach for landing, an alternating green and red light followed by a flashing red light is received from the control tower. Under these circumstances, the pilot should?
a) abandon the approach, circle the airport to the right, and expect a flashing white light when the airport is safe for landing.
b) discontinue the approach, fly the same traffic pattern and approach again, and land.
c) exercise extreme caution and abandon the approach, realizing the airport is unsafe for landing.