The Federal Reserve bond buyback

The Federal Reserve bond buyback program has buoyed Wall Street, and helped the stock market reach record highs, but yet to translate into consistent job growth across the country.

a. and helped the stock market reach record highs, but yet to translate into consistent job growth across the country
b. helped the stock market reach record highs, but it has yet to translate into consistent job growth across the country
c. helped the stock market reach record highs, and has not translated into consistent job growth across the country
d. and helped the stock market reach record highs, but it has yet to translate into consistent job growth across the country
e. and helped the stock market reach record highs, but has not translated into consistent job growth across the country

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