Explanation:

- Commonplace and unoriginal statement: This describes a remark or idea that lacks originality or insight, often repetitive or clichéd.

- Option 1: Witticism: A clever or humorous remark. Witticisms are often insightful or amusing, unlike banal statements.

- Option 2: Preamble: An introductory statement, typically preparing readers or listeners for what is to follow.

- Option 3: Prevarication: The act of lying or evading the truth. It involves being intentionally unclear or misleading.

- Option 4: Platitude: A remark that is overused and dull; lacks originality but is often presented as if it is meaningful or significant.

Your understanding seems spot on, as platitude aligns perfectly with the description of a commonplace and unoriginal statement.