I think it is B.

a = value in 97

b = value in 98

c = value in 99

b = a*(1+x/100)

c = b*(1-y/100) = a*(1+x/100)(1-y/100)

For to be c greater than a, compare c > a

a*(1+x/100)(1-y/100) > a

assuming a <> 0, if we solve the above inequality, we get to condition in B.

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