Katihar is the answer that matches the Bihar-specific fact asked in the question. nects Bihar with northeastern India. The key to this question is the precise association expressed in its wording: “Which district of Bihar is known as the 'Gateway of Bihar' due to its strategic location in the northeast?” The answer Katihar matches that clue directly and is therefore factually appropriate. Option A — Kishanganj — is incorrect because it does not match the exact person, district, location, institution, river, event or identifying feature required by the question. It may be associated with another Bihar-related context, but that broader association does not satisfy this specific wording. Option C — Purnia — is incorrect because it does not match the exact person, district, location, institution, river, event or identifying feature required by the question. Option D — Araria — is incorrect because it does not match the exact person, district, location, institution, river, event or identifying feature required by the question. Bihar GK questions frequently place neighbouring districts, related historical personalities, nearby rivers or institutions from the same field among the options. The correct method is to identify the central clue, match it with the relevant map location, historical period or official designation, and then eliminate every alternative separately. Katihar is often referred to as the Gateway of Bihar because it connects Bihar with northeastern India. Bihar GK questions frequently place neighbouring districts, rivers, historical.