Choose the most appropriate preposition to fill in the blank.
Visitors in the garden are prohibited ______ walking on the grass.

Correct option is C

The correct preposition is from.
Explanation:
We use “prohibited from” + gerund (verb-ing form) when expressing restrictions (निषेध को व्यक्त करने के लिए “prohibited from + verb-ing” का प्रयोग होता है).
Grammatical rule used: Verb + prohibited + from + verb-ing is the correct form.
(“Prohibited” के बाद “from” और फिर क्रिया का ‘ing’ रूप आता है।)
Example: Children are prohibited from entering the laboratory.
Why other options are incorrect:
· (a) For – Wrong preposition after “prohibited” (Prohibited के साथ “for” का प्रयोग नहीं होता)
· (b) To – Grammatically incorrect with “prohibited” (यह form incorrect है)
· (d) With – “With” doesn’t indicate restriction or ban (यह निषेध नहीं दर्शाता)