The correct answer B: help coworkers even if such help is not part of her job.
Organizational citizenship behavior is a person's voluntary commitment within an organization or company that is not part of their contractual tasks.
OCB deals with actions and behaviors that are not required by workers. They are not critical to their job, but they benefit the team and encourage even greater organizational functioning and efficiency. It includes being helpful and caring towards other employees in the workplace.
Jessica looks at her job as more than a paycheck, and she tries to help coworkers because she feels they might need her help. She is not expecting any personal rewards for her help, she does it for the company and the work environment. She would most likely help a newcomer adjusting to their new position or work overtime substituting a sick colleague.