Choose the best definition of temper.

Concept: As a verb, "temper" traces to the Latin temperare, "to mix in due proportion." In its everyday, non-technical use — tempering someone's words, tempering justice with mercy, tempering criticism — the verb consistently means to moderate, restrain, or ease the intensity or harshness of something by blending in a counteracting influence, rather than to increase or worsen it. (Its more technical senses, such as heat-tempering metal or glass, involve a different, specialised process and are not what is being tested here.)

Application: Applied here: among the four candidate definitions, "to soften" is the one that expresses this moderating, restraining sense — for example, "she tempered her criticism with praise" means she softened the harshness of the criticism.

Checking the other options against this sense:

• "To make worse" describes an intensifying effect (compare worsen, exacerbate) — the opposite direction from moderating.

• "To aggravate" also means to increase severity — the same opposite-direction sense as "to make worse."

• "None of the Above" does not apply once a matching definition is present among the options.

Result: Therefore "to soften" — to moderate or restrain the intensity of something — is the best definition of "temper" as used here.