Final answer:
A successful inventor of a heart valve would likely exhibit a high Need for Achievement (Nach), which corresponds to the desire to excel and succeed, as this trait is crucial for the persistence and innovation required in the invention process.
Step-by-step explanation:
You would expect a successful inventor of a new type of heart valve to have a high: c) Nach (Need for Achievement).
The question seems to be referring to McClelland's Theory of Needs, which is a motivational model that attempts to explain how the needs for achievement, power, and affiliation affect the actions of people from a managerial context. In this theory, 'Nach' stands for Need for Achievement, which is the drive to excel, to achieve in relation to a set of standards, and to strive to succeed. A successful inventor would likely have a high Nach because inventing requires creativity, persistence, and most importantly, the desire to achieve and succeed in developing something novel and effective. This personal drive is essential for overcoming obstacles and persisting through the numerous iterations of design and testing that are common in the invention process, especially with complex products such as heart valves. Knowing that their innovations have the potential to save lives or significantly improve quality of life can be a strong motivating factor for inventors with high achievement needs.