Fill in the blank with the most appropriate preposition from the options given below:
There was a long queue of people ___ the post office.

Correct option is C

The correct option is (c) at.

Explanation:
The sentence describes people waiting in a queue at a specific place — the post office. The preposition at is used to indicate presence or location at a particular point or place.

Correct answer – at:
At is used to indicate a specific location or point.
(Hindi meaning: पर / में — किसी विशेष स्थान पर)
Example: There was a long queue of people at the bank.

Grammatical Rule (English):

• At is used for specific points or places (post office, bus stop, airport).
• In is used for enclosed spaces or areas (in the room, in the city).
• On is used for surfaces or specific days/dates.

• (a) Over – Means above or across; not used to indicate location at a place.
• (b) From – Indicates origin or source; does not describe location at a place.
• (d) By – Means beside or near; while it can indicate proximity, at is the standard preposition used with institutions and public places.