Which of the following risk concepts requires an organization to determine the number of failures per year?

A.
SLE

B.
ALE

C.
MTBF

D.
Quantitative analysis

Explanation:
ALE is the annual loss expectancy value. This is a monetary measure of how much loss you could expect in a year.
Incorrect Answers:
A: SLE is a monetary value, and it represents how much you expect to lose at any one time: the single loss expectancy. SLE can be divided into two components:
AV (asset value) and the EF (exposure factor).
C: The mean time between failures (MTBF) is the measure of the anticipated incidence of failure for a system or component. This measurement determines the
component’s anticipated lifetime.
D: Quantitative analysis is used to the show the logic and cost savings in replacing a server for example before it fails rather than after the failure.

Dulaney, Emmett and Chuck Eastton, CompTIA Security+ Study Guide, Sixth Edition, Sybex, Indianapolis, 2014, pp 5, 8, 17
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