GMAT Sentence Correction (SC) | Re: Q23: A New York City ordinance of 1897 regulated the use of

In (E), is a comma between 'bicycles' and 'mandated' required? Per the rules that I have learnt, NOUN + NO COMMA + PAST PARTICIPLE = omitted relative pronoun and verb 'be' e.g. 'which had' or similar. Bicycles didn't mandate anything. Hence, I eliminated (E).

Am I confusing 'mandated' between a past participle with past simple tense?

Thanks

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