An...... is an indirect and usually unfavourable remark

Analyze the question: We need the literary term for a remark that is indirect (it hints rather than says something outright) and usually unfavourable (it suggests something negative or insulting).

Explain the concepts:

• Allusion: an indirect reference to a person, event, or work (e.g., Biblical or historical) that is not explained. It is not necessarily unfavourable.
• Irony: saying one thing while meaning the opposite, or a situation where the outcome is the opposite of what was expected. It is not defined by being indirect and unfavourable.
• Aside: words spoken by a character in a play, heard by the audience but supposedly not by the other characters.
• Innuendo: a hint or insinuation, usually derogatory, about a person or thing. It suggests something negative without stating it openly.

Solution:

• The remark is indirect, which fits both allusion and innuendo.
• The remark is usually unfavourable, which fits only innuendo.
• Irony and aside don't match the definition at all.

Example of innuendo: "I'm not saying he stole the money, but his new car appeared right after the money vanished."

Answer: The correct option is D. innuendo.

Tip: Link "innuendo" with "insinuate". Both describe hinting at something nasty without saying it directly. For "allusion", think "reference", which is neutral.