The correct answer is A) Interrupted airflow. Compressor surge is caused by a disruption or interruption in the airflow through the compressor. This can happen when the airflow is suddenly restricted or blocked, causing the compressor to lose its ability to maintain the necessary airflow. This results in the compressor stalling and potentially causing damage. The other options are incorrect because they do not directly cause compressor surge - maximum fuel pressure, low ambient air temperature, and increased demand for secondary air are not the primary factors that lead to compressor surge.