The Marginal Rate of Technical Substitution Is the Rate at Which

The marginal rate of technical substitution is the rate at which

A) one product can be substituted for another without affecting total production cost
B) one product can be substituted for another without affecting total expenditure by the buyer
C) one product can be substituted for another without affecting total utility
D) one input can be substituted for another without affecting total production cost
E) one input can be substituted for another without affecting total output