In Medieval Europe, an Important Technological Advance Was the Use

Multiple Choice

In medieval Europe, an important technological advance was the use of the padded horse collar for plowing. Once this idea was thought of, other people used it. What does this example illustrate about knowledge?

A) It is generally a public good.
B) It is generally a societal good.
C) It is generally a private good.
D) It is generally a normal good.