An individual who suffers from panic disorder might become anxious about climbing stairs, exercising, or being in hot rooms because these activities produce sensations similar to those accompanying a panic attack. in psychological terms, the exercise and hot rooms have become

I believe the answer is: conditioned stimuli

Conditioned stimuli refers to the things that becomes a trigger that cause a certain type of response after the process of classical conditioning ( in which the subject who previously see the trigger as neutral stimulus started to change its response after the netural stimulus is paired with unconditioned stimulus over and over again)

hygrometers and hair thermometers (often found as part of hygrometers/psychrometers) can be used to measure humidity. barometers are used to measure atmospheric pressure, while anemometers are used to measure wind speed. so the 2nd and 4th choices should be the correct answers.