All Else Equal,if There Are Diminishing Returns,then If a Country

Multiple Choice

All else equal,if there are diminishing returns,then if a country raised its capital by 100 units last year and by 100 units this year,

A) the increase in output was greater for this year than last year.
B) the increase in output was greater last year than this year.
C) the increase in output is the same in both years.
D) None of the above is necessarily correct.