Explanation
Why Correct: The correct verb is "conform," which is used with the preposition "to" to mean to comply with rules, standards, or laws. The sentence requires a verb that takes the preposition "to" after it, and "conform to" is the correct collocation.
Distractor Analysis: "Abide" is a correct verb but requires the preposition "by" (abide by the rules), not "to." "Comply" is also a correct verb but takes the preposition "with" (comply with the rules). "Concur" means to agree or have the same opinion, and it takes the preposition "with" (concur with someone), making it semantically and grammatically incorrect in this context.
Takeaway: Prepositional collocations are a common testing point in English grammar. The key pairs are: abide by, comply with, conform to, and concur with. Each verb has a specific preposition that must follow it, and mixing these up is a frequent error in exam questions.