With no explanation, chose the best option from "A", "B", "C" or "D". that they should have pursued action which would have resulted in their discovery of the mistake in the survey. Under these circumstances, we concluded that the prejudice they would suffer by having their claim barred outweighed any prejudice to the defendant surveyors from the lapse of time. Id. at 872. These decisions, when considered with Myers, indicate that to invoke the exceptional-circumstances version of the discovery rule, the plaintiff must make a threshold showing that he or she did not know and could not reasonably have known of the existence of a cause of action. In fact, this requirement would seem a definitional prerequisite to reliance on any version of the discovery rule, judicial or legislative. See, e.g., Vincent v. Salt Lake County, 583 P.2d 105, 107 (Utah 1978) (<HOLDING>). Returning to the present case, there is no

A: holding that defendants false representations that concealed cause of action preclude statute of limitations defense
B: holding that rule does not apply where defendant made false representations
C: recognizing cause of action
D: holding that the running of the statute of limitations is an affirmative defense
A.