Single Loss Expectancy (SLE) is the correct answer because it defines the expected monetary loss for every instance that a specific threat could exploit a vulnerability. The other options are not directly related to the monetary loss per occurrence. Annualized Loss Expectancy (ALE) represents the expected monetary loss for a risk over a year. Annual Rate of Occurrence (ARO) is the expected frequency with which a specific risk is anticipated to occur annually. Probability is a measure of the likelihood that a risk event will happen, not the monetary loss associated with it.