## **Core Concept**
The Nd:YAG (Neodymium-doped Yttrium Aluminum Garnet) laser is a type of laser that uses a neodymium-doped yttrium aluminum garnet crystal as its gain medium. The wavelength of a Nd:YAG laser is a critical property that determines its applications in medicine and industry. The Nd:YAG laser emits infrared light.

## **Why the Correct Answer is Right**
The Nd:YAG laser has a characteristic wavelength of **1064 nm**. This specific wavelength is due to the energy transitions within the neodymium ions doped into the yttrium aluminum garnet crystal. The 1064 nm wavelength is in the infrared part of the electromagnetic spectrum, which allows it to be used for various applications, including laser-induced breakdown spectroscopy, laser cutting, and certain medical procedures like laser trabeculoplasty for glaucoma.

## **Why Each Wrong Option is Incorrect**
- **Option A:** (Ultraviolet range) - This is incorrect because Nd:YAG lasers do not emit in the ultraviolet range; they emit in the infrared range.
- **Option B:** (Visible range, specifically green light) - This is incorrect because, although some lasers do emit in the visible spectrum, the Nd:YAG laser specifically emits at 1064 nm, which is infrared.
- **Option D:** (Another infrared wavelength) - This option is incorrect because it does not match the known emission wavelength of a Nd:YAG laser.

## **Clinical Pearl / High-Yield Fact**
A key clinical application of the Nd:YAG laser is in ophthalmology for procedures like posterior capsulotomy after cataract surgery. The **1064 nm** wavelength allows for precise treatment with minimal damage to surrounding tissues.

## **Correct Answer:** C. 1064 nm.