Which of the following factors most contributes to the U$.$S$.$ automotive industry being characterized by high entry barriers? Question $15$ options: A$)$ New auto companies create electric cars powered by simpler motors and gearboxes. B$)$ New entrants in the automotive industry expect that incumbents will not or cannot retaliate. C$)$ Car manufacturers require large$-$scale production in order to be cost$-$competitive. D$)$ Few industrial products are as easy to build as cars powered by internal combustion engines.