Consider an Aggregate Production Function Y = F(K,L)that Displays Diminishing

Consider an aggregate production function Y = F(K,L) that displays diminishing marginal returns to labour.If the amount of capital is held constant and the amount of labour used in production is increasing,then

A) each additional unit of labour will add less to total output than the previous unit of labour.
B) each additional unit of labour will add more to total output than the previous unit of labour.
C) total output increases in proportion to the increases in labour.
D) there are increasing returns to scale.
E) there are constant returns to scale.