The boy came through the window as stealthily as he could.

Analyze the question: You are asked for the word closest in meaning to "stealthily" in the sentence "The boy came through the window as stealthily as he could."

Explain the concept: "Stealthily" is the adverb form of "stealth." It means acting in a cautious, quiet, secret way so that no one notices you. The key idea is not being heard or detected. Think of a thief creeping in at night.

Solution, option by option:

• A. quietly means making little or no noise. This matches the main idea of stealth, which is avoiding being heard or noticed. ✔
• B. carefully means paying close attention to avoid mistakes or harm. Someone can be careful without being secretive, such as a surgeon or a driver, so this is not the same as stealth.
• C. quickly means at speed. Stealth has nothing to do with speed.
• D. slowly means at a low speed. A person moving stealthily may move slowly, but slowness is not the meaning of the word.

Answer: The nearest in meaning is A. quietly.

Tip: For vocabulary questions, ask, "What is the core idea of the word?" For "stealthily," the core idea is secret and silent. Remember: stealth = silent and secret. Be careful with "carefully," which is a tempting distractor, but it describes caution in general rather than quietness or secrecy.