I have decided to go into the business of making football helmets. In doing so$,$ I am well aware that helmets are primarily intended to protect against skull fractures and that they cannot prevent brain injuries $($like concussions$).$

In light of this knowledge:

I have a duty to warn consumers that my product can still be dangerous, even if used properly.

I have a duty to warn consumers that my product is only dangerous if used improperly. It was designed to prevent fractures, not concussions, and it is effective at doing that.

I have no duty to warn consumers of dangers related to my product. It is plainly obvious that football is a violent game and that injuries may occur. They assume the risks of playing.

I have no duty to warn consumers of dangers related to my product as long as there are no obvious design or manufacturing defects.