The correct answer is option 3, J. L. Baird.
Option 1, Alexander Graham Bell, is known for his invention of the telephone, not the movie projector.
Option 2, Benjamin Franklin, is famous for his contributions in the field of electricity, but he did not invent the movie projector.
Option 4, Thomas Edison, is often associated with the invention of the movie projector, but this is not accurate. While Edison did make significant improvements to the design and functionality of the movie projector, he did not invent it.
John Logie Baird, a Scottish engineer, is credited with inventing the first working mechanical television system, which included a device called the "televisor" that functioned as a crude movie projector. He made the first public demonstrations of this invention in the 1920s. This makes him the correct answer to the question of who invented the movie projector.