Which of the Following Is a Reason for Diminishing Rather

Multiple Choice

Which of the following is a reason for diminishing rather than constant returns to specialization?

A) All resources are of the same quality.
B) Resources can shift from the production of one good to another seamlessly.
C) Each country has a fixed stock of resources.
D) Different goods use different resources in different proportions.
E) Trade does not affect the distribution of income within a country.