A person who sneaks into a country
Answer: Option A
Solution(By Examveda Team)One word substitute is Infiltrator.
Infiltrator: a person who enter or gain access to (an organization, place, etc.) surreptitiously and gradually, especially in order to acquire secret information.
Sniper: a person who shoots from a hiding place, especially accurately and at long range.
Invader: a person or group that invades a country, region, or other place.
Aggressor: a person or country that attacks another first.
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