3.1 Energy Exists In Different Forms.

Plants use energy from the sun to grow. This is because they undergo a process called photosynthesis, where they convert sunlight, carbon dioxide, and water into glucose and oxygen. This glucose serves as their source of energy for growth and development. Therefore, both "Plants" and "plants" are correct answers as they refer to the same group of organisms that utilize solar energy for their growth.

Energy is the ability to cause change. It can be transformed from one form to another and is required for any kind of work or movement to occur. Motion refers to the change in position of an object, force refers to a push or pull on an object, and sound refers to the vibrations that travel through a medium. While all of these concepts are related to the idea of causing change, energy is the most general and encompassing term.