‘A plant is a vegetable organism' is an example of

The correct answer is C) Synonymous definition. A synonymous definition explains a term by giving another word of nearly the same meaning. Here "plant" is explained through "vegetable organism", a near-equivalent phrasing, so the definition works by substitution of meaning rather than by picking out a distinctive feature.

• A) Figurative definition is wrong. It uses metaphor or comparison, as when a brave man is called a lion, and nothing here is figurative.
• B) Negative definition is wrong. It says what a thing is not, such as defining a non-vegetarian as one who does not eat only plants. This sentence states what a plant is.
• D) Accidental definition is wrong. It describes a thing by an incidental property, such as defining man as a clothed animal. That is not the pattern here.

The core concept is the classification of definitions in logic, which is part of the general aptitude and reasoning foundation for Mains and for interview questions on precise thinking. Aspirants should know the types cleanly, because the same distinctions help in answering questions on terms like "development" or "federalism".

Trap: Candidates confuse a synonymous definition with a genus-and-differentia definition, since "organism" looks like a genus. Check whether the sentence gives a substitute word for the term, which is the test here.