In New Theories of Economic Growth, "Learning by Doing" Contributes

In new theories of economic growth, "learning by doing" contributes to endogenous technological change because

A) "learning by doing" increases the marginal product of physical capital.
B) information at all stages of the design and production processes is fed upstream and contributes to further innovation.
C) new technical knowledge can be transferred at zero cost.
D) knowledge can be considered a public good.
E) knowledge can be considered a private good.