While in treatment for panic disorder, Leroy is asked to engage in behaviors that activate the sympathetic nervous system. In other words, Leroy is engaging in behaviors that produce the physical sensation of fear. What type of treatment does this appear to be?

Interoceptive Exposure

Explanation:

Interoceptive exposure is a cognitive behavioral therapy technique used in the treatment of panic disorder. It refers to carrying out exercises that bring about the physical sensations of a panic attack, such as hyperventilation and high muscle tension, and in the process removing the patient's conditioned response that the physical sensations will cause an attack to happen. I got this from Wikipedia.

d - failures.

the only attempted british colony in north america before 1600 was roanoke, virginia, which was a total failure. england claimed several areas, including newfoundland, but made no sustainable attempts to colonize them before 1600.