Which of the following terms is BEST described by the definition below?

Comprehensive and Detailed Explanation From Exact Extract:

The SRE Book defines reliability as: “the probability that a system will perform its intended function correctly for a specified period of time.” (SRE Book – Introduction). Reliability focuses on correctness and consistent performance, not simply uptime. Availability (option A) refers to system uptime or accessibility. Durability (option C) refers to long-term data persistence. Throughput (option D) measures volume of work processed over time.

Because the definition explicitly mentions probability of meeting performance standards and correct output over time, it directly matches the SRE definition of reliability.

Thus, B is correct.