Sentence Correction (SC) | Re: The widely accepted big-bang theory holds that the universe began in a

A —> began (past simple) and has been expanding (present perfect continuous). This tense use is correct as the beginning happened in an instant in the past; whereas, its expansion started from that moment and it is still ongoing. The use of the present perfect continuous is correct, it only emphasises the universe expansion.

All these other choices have a wrong use of the tenses

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