Maria is studying in a kitchen where a noisy ceiling fan spins above her. after an hour, maria no longer pays attention to the fan. what explains her current response?

Her current situation is explained by sensory adaptation.

Sensory adaptation it's when the sensitivity to a stimulus decreases as a consequence of constant exposure to the stimulus.
When the stimulus starts, the neurons will begin firing action potentials. After a while in the same environment, you'll most likely have forgotten all about that sensation (in this case the fan noise) even though the stimulus is exactly the same.

True. you know, tools like shovels.

C. equitable; undue influence