Final answer:
OPTION A.
Pilots should climb or descend as rapidly as practicable to 1,000 feet above or below their assigned altitude, then continue at a rate of 500 to 1,500 feet per minute until reaching the assigned altitude to comply with ATC instructions.
Step-by-step explanation:
To comply with ATC (Air Traffic Control) instructions for altitude changes of more than 1,000 feet, the expected practice is that pilots should climb or descend as rapidly as practicable up to 1,000 feet above or below their newly assigned altitude. Once achieving that intermediate level, pilots should then adjust their rate of climb or descent to between 500 and 1,500 feet per minute until they reach the assigned altitude. This method ensures an efficient transition to the assigned altitude while maintaining a safe and manageable aircraft performance. It is also consistent with the need to follow ATC instructions precisely for safety and traffic flow purposes.