API 580, in Section 5.1 and throughout the risk evaluation process, uses the term “risk driver” to refer to dominant contributors to the overall risk ranking or score. Specifically:

“The expected outcome from the application of the RBI process should be the linkage of risks with appropriate inspection… The RBI process is capable of generating: … identification of risk drivers.”

These risk drivers are the key parameters (such as a specific damage mechanism, operating condition, or component failure mode) that most significantly impact either the probability or the consequence component of the risk. Hence, the correct interpretation aligns with Option A.