Final answer:
The correct word to complete the sentence is 'resilience', which signifies the capacity to recover from difficulties; this trait is crucial for career success. 'Mercy' is not one of Benjamin Franklin's thirteen virtues.
Step-by-step explanation:
The correct word to fill in the blank in your sentence is 'resilience'. Resilience refers to the ability to recover quickly from difficulties or setbacks, and it plays a pivotal role in one's career success. The term 'fragility' indicates delicateness and is opposite to the context of the sentence. 'Flexibility' relates to adaptability but does not specifically convey the idea of recovery from hardship. 'Vulnerability' means being open to being harmed or attacked and again does not fit the context. Therefore, 'tenacity' could seem a close choice, but as it refers more to the steadfastness or persistence rather than the ability to recover, 'resilience' is the more appropriate choice given the context of overcoming an attack and achieving success.
Regarding Benjamin Franklin's thirteen virtues, 'mercy' was not listed among them. Franklin's virtues were designed to guide his personal development and included values such as sincerity, temperance, and tranquility. As such, options A, B, and D were, in fact, included in Franklin's list of thirteen virtues.