Final answer:
The clearance provided under Type 3 control for attacking aircraft is Routine clearance, allowing for multiple attacks under specific parameters without individual clearances for each attack.
Step-by-step explanation:
The brevity provided to attacking aircraft for clearance during a Type 3 control is C) Routine clearance. In combat or training exercises, Type 3 control is a method of terminal attack control where the Ground Commander authorizes multiple attacks within a specific block of airspace or a target area without the need for further clearance for each individual attack. It provides greater flexibility and expediency in operations, especially in situations with a high volume of air traffic or multiple targets. However, it requires that all criteria outlined in the rules of engagement and any specific restrictions be met before clearance is given.