Which sentence shows faulty parallelism?

Correct option is A

The error lies in option (a).

• Explanation: The sentence contains a series: “planning, coordination, and to execute carefully.” The first two items are nouns/gerund-like nominal forms, but the third item is an infinitive phrase.
• This breaks parallel structure because items in a series should be in the same grammatical form.
• A correct version could be: “The project requires planning, coordination, and careful execution.”

Grammatical rule (English):
• In parallelism, words or phrases joined in a series must have the same grammatical form.
• Nouns should be matched with nouns, gerunds with gerunds, and infinitives with infinitives.

व्याकरण नियम (Hindi):
• Parallel structure में एक ही शृंखला के सभी पदों का व्याकरणिक रूप समान होना चाहिए।
• यदि दो शब्द noun form में हैं, तो तीसरा भी noun form में होना चाहिए; अलग form आने पर त्रुटि होती है।

Explanation of Other Options:
• (b): All three items are parallel infinitive forms.
• (c): Both verb phrases are parallel infinitive structures.
• (d): All three items are in parallel gerund form.

So the correct answer is (a)