Step 1: Understanding Categorical Syllogism.
A categorical syllogism consists of three categorical propositions (two premises and one conclusion) and has exactly three terms: the major term, minor term, and middle term. These three terms are used in a logical relationship to derive the conclusion.
Step 2: Analyzing the Options.
- 1. It has three premises: This is incorrect. A syllogism always has two premises, not three.
- 2. It has three terms: This is correct. A categorical syllogism has three distinct terms: the major term, minor term, and middle term.
- 3. It has three figures: This refers to the different ways the terms can be arranged in a syllogism, but it's not a defining attribute.
- 4. It has three moods: Moods are specific forms of syllogisms, but not a basic attribute.
Step 3: Conclusion.
The correct answer is 2. It has three terms.
Final Answer:
\[
\boxed{\text{The correct answer is 2. It has three terms.}}
\]