Topic: Adjective (বিশেষণ),

Best Answer Explained in Below-:

In the context of the question "Which word is an adjective?", it's important to understand the function and definition of adjectives. Adjectives are words that describe or modify nouns, providing additional information about them, such as their qualities, quantities, or states.

Looking at the provided options:

A) **Honesty** - This is a noun that refers to the quality of being truthful and sincere. It does not describe or modify any other word.

B) **Beauty** - This is also a noun, representing the quality of being pleasing in appearance or nature. Like honesty, it does not serve to modify another word.

C) **Lunar** - This is an adjective that means "related to the moon." It can be used to describe nouns, such as in the phrases "lunar surface" or "lunar cycle," indicating something associated with or characteristic of the moon.

D) **Pole** - This is a noun that refers to either the ends of something (like the poles of the Earth) or a long, slender piece of material (like a flagpole).

Therefore, the only word in the list that functions as an adjective is **C) Lunar**, making it the correct answer.