Sentence Correction (SC) | Re: Britain's economic growth was slower in the mid-1970's and

Doing away with extra words in the sentence gives actual answer:
d) The economy of Britain grew slowly and declined more rapidly than did the economy of the United States. parallel with correct tense.
e). Britain's economy grew slowly and its decline was more than the economy of the United States. what does its refer to? Britain or economy? Not clear.

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