Answer: A.) are reasonable and testable
A hypothesis can be defined as the supposition or assumption of scientific process that is based on limited scientific evidences and used as a starting point for further investigation. The hypothesis needs to be proved by following relevant scientific methodology.
In the given situation, both the hypothesis are correct because both warm temperature and sunlight are genuinely responsible for wilting of plant in nature. The effect of both sunlight and warm temperature can be tested separately on plant. This proves that the hypothesis are reasonable and testable.