What is the test for determining whether a defendant owes a duty of care to a plaintiff?

The "duty analysis" is based upon a distinction between (1) the situation where the assumption of risk doctrine embodies a legal conclusion that there is no duty on the part of the defendant to protect the plaintiff from a particular risk, known as "primary assumption of risk," and (2) the situation where the defendant owes a duty of care to the plaintiff but the plaintiff knowingly encounters a risk of injury caused by the defendant's breach of that duty, known as "secondary assumption of risk." Whether the defendant owes a legal duty to protect the plaintiff from a particular risk of harm depends on the nature of the activity in which the defendant is engaged and the relationship of the defendant and the plaintiff to that activity. (Knight v. Jewett, supra, 3 Cal.4th at p. 309, 11 Cal.Rptr.2d 2, 834 P.2d 696.) The existence and scope of the defendant's duty of care is a legal question to be decided by the court rather than the jury. (Id. at p. 313, 11 Cal.Rptr.2d 2, 834 P.2d 696.)