According to the quantum theory of light, the energy of light is carried in discrete units are called A. Photoelectrons B. Protons C. Electrons D. Photons

The correct answer is: D. Photons

Photons are elementary particles in quantum mechanics that mediate the electromagnetic force, the fourth fundamental force (not including gravity) binding together charged particles. A photon has zero rest mass and carries an electric charge of 0 elementary charge. It

Photons are emitted when an atom or molecule is excited to a higher energy state and then decays back to a lower energy state. The energy of the photon is equal to the difference between the two energy states. Photons can also be absorbed by atoms or molecules, causing them to be excited to a higher energy state.

Photons are used in a variety of technologies, including lasers, light-emitting diodes (LEDs), and solar cells. They are also essential for vision, as they are the particles that carry light to our eyes.

The other options are incorrect because:

• A. Photoelectrons are electrons that are ejected from a metal surface when light is shone on it.
• B. Protons are positively charged particles that are found in the nucleus of an atom.
• C. Electrons are negatively charged particles that are found in the atom’s electron cloud.