Step 1: Identify a releasing agent. A releasing agent, also known as a mold release, is a material applied to a mold's surface to stop the casting material from adhering, which allows for simple extraction.
Step 2: Evaluate the choices. Commonly used substances for a non-stick barrier include liquid detergent, oils, and waxes. Alum (potassium aluminum sulfate) is a chemical utilized in applications such as water purification and dyeing as a mordant, but it is not employed as a mold release agent.