​____________ is a device by which two different photographs of the same object can be viewed together. ​

Correct option is A

The correct answer is (A) Stereoscope.

Explanation:
A stereoscope is a device that allows two different photographs of the same object to be viewed together, creating a three-dimensional effect.

Incorrect Options Explanations:

• Stroboscope: Used to observe moving objects by producing flashes of light.
• Stethoscope: A medical instrument used to listen to heart and lung sounds.
• Spectroscope: Used to study the spectrum of light emitted by substances.

Information Booster:

• Stereoscope: Developed by Charles Wheatstone in 1838 to provide a 3D view from two photographs taken at different angles.
• Key Point: The stereoscope is commonly used in photography and visual perception studies.