Laser is/ are

Options

A. Highly coherent
B. Highly monochromatic
C. Highly directional
D. All of these

Answer

To answer the question "Laser is/are," we need to analyze the properties of lasers and determine the correct grammatical form based on the context. Here’s a step-by-step breakdown of the solution:

### Step 1: Understanding the term "Laser"
- The term "laser" stands for "Light Amplification by Stimulated Emission of Radiation." It is a noun that refers to a device that emits light through a process of optical amplification.

### Step 2: Analyzing the grammatical number
- The word "laser" is singular. Therefore, when referring to it in a sentence, we should use "is" instead of "are."

### Step 3: Identifying the properties of lasers
- Lasers have several key properties:
1. **Monochromatic**: Lasers emit light of a single wavelength.
2. **Coherent**: The light waves emitted are in phase.
3. **Polarized**: The light waves vibrate in a single plane.
4. **Collimated**: The light beams are parallel and travel in one direction.
5. **High Energy**: Lasers produce light with high energy.

### Step 4: Evaluating the options
- The options provided in the question likely refer to the properties of lasers. Since lasers exhibit all the mentioned properties, we can conclude that:
- Option 1: Highly coherent - True
- Option 2: Highly monochromatic - True
- Option 3: Highly directional - True
- Option 4: All of these - True

### Step 5: Conclusion
- Since "laser" is singular, the correct phrase is "Laser is." The correct answer regarding the properties of lasers is that they are all true, hence the best choice is "All of these."

### Final Answer:
**Laser is** (singular) and the properties include highly coherent, highly monochromatic, and highly directional.

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