Assertion (A) : Quartz prism is used to study ultraviolet spectrum.

Reason (R) : Quartz does not absorb ultraviolet radiations.

1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true and (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false and (R) is true.

Both (A) and (R) are true and (R) is the correct explanation of (A).

Explanation

Assertion (A) is true because glass absorbs ultraviolet (UV) radiation, so it cannot be used in prisms or lenses for UV studies whereas quartz, on the other hand, allows UV light to pass through, making it suitable for dispersing and studying the UV spectrum.

Reason (R) is true because quartz is transparent to ultraviolet light down to wavelengths of about 200 nm (far UV) so it does not absorb UV radiation, which is why it's preferred for UV applications.