The Marketing of the First Ballpoint Pen by Milton Reynolds

The marketing of the first ballpoint pen by Milton Reynolds showed

A) that first-mover advantages can make it more difficult for new firms to enter a market and compete against the first mover.
B) that being the first firm to market a new product can result in a natural monopoly.
C) that being the first firm to market a product may not lead to a long-lived advantage over later entrants into the market.
D) how important it is to receive patent protection for a new product.