Final answer:
The term 'insulates' means to trap heat within an object or system, in this context, a sweatshirt preventing body heat from escaping. Clothing acts as insulation by slowing down heat transfer through processes like conduction and convection.
Step-by-step explanation:
The word insulates in the sentence refers to the sweatshirt's ability to trap heat inside rather than allowing it to escape to the surrounding environment. The appropriate answer to the question posed would be option c, which states that insulating something means trapping heat inside. Insulation is important to maintain a comfortable body temperature by reducing the rate of heat transfer. In winters, it prevents heat from moving out, while in summers, it can prevent external heat from warming the inside of a house or in this case, the body.