Fact 1: If an object reflects light toward the eye then that object can be seen.

Fact 2: Light is made of photons .

Given the two facts above, answer the question "An object can be seen if it reflects what?" with the following options: 
- Energy.
 - vibrations
 - energy
 - waves
 - sound
 - sun's heat
 - photons
 - sunlight


 

       photons  