Dev, Clara, and Marcus are researchers working at a biotechnology firm under extreme pressure to develop a new vaccine.

• Dev is highly competitive, constantly looks at his watch, and frequently reacts with anger when lab equipment malfunctions.
• Clara remains relaxed and patient, even when experiments fail, and refuses to let work pressure affect her personal life.
• Marcus is highly dedicated to the mission, views unexpected budget cuts as an exciting opportunity to innovate, and firmly believes that the team's daily efforts will determine the project's success.

Discuss personality types and hardiness as explanations for individual differences in resistance to stress. Refer to Dev, Clara, and Marcus in your answer.