D because I learned this 2 years ago
ANSWER:
What is the difference between heat and light? - Physics Stack ... Heat and light are different but they are both forms of energy. Heat is a form of kinetic energy contained in the random motion of the particles of a material. Light is a form of electromagnetic energy. As with other forms of energy, heat energy can be transformed into light energy and vice versa.
In optics, a diaphragm is a thin opaque structure with an opening (aperture) at its center. The role of the diaphragm is to stop the passage of light, except for the light passing through the aperture.
A). Both the energy and the wave travel in the same direction.
If they didn't, they'd wind up in different cities almost instantly.