Select the most appropriate option to substitute the underlined segment in the given sentence. If no substitution is required, select No improvement. Over the past 20 years, there has been a constant decline in the variety of vegetables that we eat because the native varieties are no longer available. (a) No improvement (b) had been (c) was been (d) is being

Options

A. No improvement
B. is being
C. was been
D. had been

Answer

A