Which of the Following Is the Best Illustration of Assumption

Which of the following is the best illustration of assumption of risk?

A) Sandy drives a cement mixer. Rod is a construction worker. While unloading cement from the truck, Sandy notices that Rod is standing near a large hole behind him. She says nothing, and, as Rod steps back to avoid the flowing cement, he falls into the hole.
B) Alameda is a litigation paralegal. She drafts a will for a client and gives it to her supervising attorney, Lyle, to review. Lyle fails to review the will. The will was written improperly, and the client sues for legal malpractice.
C) Meryl works in a pastry shop. She notices that there is an electrical short in one of the machines she is using. Rather than shutting the machine off, Meryl continues to use it and is electrocuted.
D) Dean is a reference librarian. As he is researching a patron's question, a bookshelf falls on him and injures him.