Pretend you are a teacher preparing a quiz for the text I will provide. 
            Each quiz question should follow the format below. 
            Ensure that you carefully recheck the questions and answers for accuracy. 
            The output should be a ready-to-use list of dictionaries for the Python eval function:

            [

                    "question": "WRITE THE QUESTION HERE",
                    "options": ["A) OPTION_1", "B) OPTION_2", "C) OPTION_3", "D) OPTION_4"],
                    "answer": INDEX_OF_CORRECT_ANSWER_IN_OPTIONS_LIST,
                    "explanation": "EXPLAIN WHY THE ANSWER IS CORRECT"

            ]

            Text:
            avelength & Frequency 
Angle of incidence 
Nature of a medium 
Intensity of radiation. 
Shorter wavelengths will have higher energy and frequencies and low depth of penetration and greater absorption in superficial tissue. 
The Characteristics of Light 

laser in medicine
History of laser
The word laser is an acronym for Light Amplification by the Stimulated Emission of Radiation. 
Laser light today covers a wide range of wavelengths, which includes the visible range of the electromagnetic spectrum .
In medicine, it became the "beam that heals" and has been utilized in nearly every discipline of medicine, in diagnosis, therapy, surgery and medical instrumentation.


Basic Components of Laser 
Laser system consists of three important parts. 
1. Active medium or laser medium 
2. An energy source (referred to as the pump or pump source) 
3. An optical resonator consisting of a mirror or system of mirrors



Types of lasers
Lasers are classified into 4 types based on the type of laser medium used:
Solid-state laser
Gas laser
Liquid laser
Semiconductor laser

Types of lasers
Solid-state laser
A solid-state laser is a laser that uses solid as a laser medium. In these lasers, glass or crystalline materials are used. Ions are introduced as impurities into host material which can be a glass or crystalline. The process of adding impurities to the substance is called doping. Rare earth elements such as cerium (Ce), erbium (Eu), terbium (Tb) etc are most commonly used as dopants.
Types of lasers
Solid-state laser
Materials such as sapphire (Al2O3), neodymium-doped yttrium aluminum garnet (Nd:YAG), Neodymium-doped glass (Nd:glass) and ytterbium-doped glass are used as host materials for laser medium. Out of these, neodymium-doped yttrium aluminum garnet (Nd:YAG) is most commonly used. The first solid-state laser was a ruby laser. It is still used in some applications. In this laser, a ruby crystal is used as a laser medium. 
In solid-state lasers, light energy is used as pumping source. Light sources such as flashtube, flash lamps, arc lamps, or laser diodes are used to achieve pumping.
Types of lasers
Gas laser
A gas laser is a laser in which an electric current is discharged through a gas inside the laser medium to produce laser light. In gas lasers, the laser medium is in the gaseous state.  
Gas lasers are used in applications that require laser light with very high beam quality and long coherence lengths.
In gas laser, the laser medium or gain medium is made up of the mixture of gases. This mixture is packed up into a glass tube. The glass tube filled with the mixture of gases acts as an active medium or laser medium.
Types of lasers
Liquid laser
A liquid laser is a laser that uses the liquid as laser medium. In liquid lasers, light supplies energy to the laser medium. 
A dye laser is an example of the liquid laser. A dye laser is a laser that uses an organic dye (liquid solution) as the laser medium. 
A dye laser is made up of an organic dye mixed 

            Quiz: