Correct option is C
The error lies in option (c).
• Explanation: The verb 'prohibit' takes a fixed prepositional pattern. It must always be followed by the preposition 'from' and a gerund (V + ing). Therefore, using 'against joining' is grammatically incorrect, and it must be replaced with 'from joining'.
• Thus, the error lies in the choice of preposition, and it is corrected by replacing 'against' with 'from'.
• Grammatical rule (English): The verb 'prohibit' follows the structural construction: 'Prohibit someone + from + gerund (V + ing)'.
• व्याकरण नियम (Hindi): 'Prohibit' क्रिया के बाद हमेशा 'from' प्रीपोज़िशन और उसके बाद gerund (V + ing) का प्रयोग होता है, न कि 'against' का।
So the correct answer is (c)