Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: Most hormones are produced by the endocrine system.

Output: Most hormones are produced by which human organ system?


Input: Consider Input: Absorption is the process by which the substances you consume are taken up by the blood.

Output: What is the process by which the substances you consume are taken up by the blood?


Input: Consider Input: Voltage is continuously changing within a circuit in an analog signal.
Output: What is continuously changing within a circuit in an analog signal?