Sentence Correction (SC) | Re: India is a country with at least fifty major regional languages, of

HelloIotaa ,

We hope this finds you well.

To answer your query, Option E incorrectly refers to the noun "languages" with the pronoun "whom"; remember, "who" and "whom" can only be used to refer to human beings.

To understand the use of "Who" and "Whom" on GMAT, you may want to watch the following video (~2minutes):

[you-tube]
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