Final answer:
The three factors to determine undue hardship are cost, outside sources of funding, and health and safety requirements, making option A the correct answer.
Step-by-step explanation:
The three factors used to determine undue hardship in various legal contexts, such as when assessing if an accommodation causes undue hardship on an employer under the Americans with Disabilities Act, typically include: cost, outside sources of funding, and health and safety requirements. Therefore, the answer to the question is A. Cost, outside sources of funding, health and safety requirements. These three factors are considered to evaluate whether providing an accommodation would be too burdensome for an employer. It is a balance between the needs of the individual and the impact on the operations of the employer.