Answer:

The given sentence states that "She thought of a wise plan". In this sentence, the word "thought" is used as a verb. Let's understand the concept and usage of verbs, adverbs, and adjectives to determine the correct answer.

Verbs:
- Verbs are words that express an action, occurrence, or state of being.
- They are the main part of a sentence and can be used to describe actions (e.g., run, think, eat) or existence (e.g., is, am, are).
- Verbs can be used in different tenses (past, present, future) and forms (base form, past tense, present participle, past participle) to convey different meanings.

Adverbs:
- Adverbs are words that modify or describe verbs, adjectives, or other adverbs in a sentence.
- They provide additional information about the action or manner in which something is done.
- Adverbs often end in "-ly" and can answer questions like "how," "when," "where," or "to what extent."

Adjectives:
- Adjectives are words that describe or modify nouns or pronouns in a sentence.
- They provide more information about the noun by giving details about its size, color, shape, etc.
- Adjectives can be used to answer questions like "what kind," "which one," or "how many."

Analysis:
In the given sentence, the word "thought" is used to describe an action performed by the subject "she." It represents the mental process of thinking and coming up with a plan. Therefore, "thought" is used as a verb in this context.

Conclusion:
Based on the analysis, we can conclude that the correct answer is option 'A' - verb.

Verb