**The reasoning**
The word "quickly" modifies the verb "ran" — it tells us *how* she ran. Words that modify (describe) verbs, adjectives, or other adverbs are called **adverbs**.
Here's the test: Ask yourself "How did she run?" The answer is "quickly." That "-ly" ending is your major clue — most adverbs in English end in -ly (quickly, slowly, carefully, beautifully). Since "quickly" describes the *manner* of the action (running), it's an **adverb**.
**Why the wrong options tempt you**
- **Adjective** seems close because both adjectives and adverbs are describing words, but adjectives only describe *nouns* (a quick girl), not verbs.
- **Noun** might confuse you if you think any important word is a noun, but nouns name people, places, or things — "quickly" doesn't.
- **Pronoun** is unlikely, but students sometimes mix up word types when rushed.
**Quick takeaway**
If a word tells you *how, when, where,* or *to what extent* an action happens, and especially if it ends in -ly, it's an adverb modifying the verb.