Time left $0$:$34$:$33$

Ethan is a heavy equipment operator for Acme Construction, Inc. Ethan suffered a head injury when the bull dozer he was operating slipped out of gear and lurched to a stop. Ethan was not wearing his hard hat at the time of the injury, and he would not have been hurt as badly if he had been wearing his hard hat. Ethan sued the manufacturer under strict product liability. If the manufacturer claims that Ethan was negligent for not wearing his hard hat at the time of the injury, the manufacturer is asserting the defense of:

Select one:

a$.$ assumption of risk.

b$.$ comparative negligence.

c$.$ commonly known$-$danger.

d$.$ preemption.