The crystal system having rectangular prisms is

Options

A. Triclinic
B. rhombic
C. trigonal
D. Hexagonal

Answer

To determine the crystal system that has the characteristic of a rectangular prism, we can analyze the properties of the given options.

### Step 1: Understand the Definition of a Rectangular Prism
A rectangular prism is characterized by having three dimensions where the lengths of the sides are not necessarily equal. This means that the angles between the sides are right angles, but the lengths can vary.

### Step 2: Analyze the Given Crystal Systems
The options provided are:
- Triclinic
- Rhombic
- Trigonal
- Hexagonal

### Step 3: Identify the Characteristics of Each Crystal System
1. **Triclinic**: In this system, the sides are unequal and the angles are not right angles. This does not correspond to a rectangular prism.

2. **Rhombic (Orthorhombic)**: This system has three unequal axes that are all at right angles to each other. This matches the definition of a rectangular prism.

3. **Trigonal**: This system has three equal axes that are inclined at angles other than 90 degrees, which does not correspond to a rectangular prism.

4. **Hexagonal**: This system has four axes, three of which are equal and lie in a plane at 120 degrees to each other, and one that is perpendicular to this plane. This does not correspond to a rectangular prism.

### Step 4: Conclusion
Based on the analysis, the crystal system that has the characteristic of a rectangular prism is the **Rhombic (Orthorhombic)** system.

### Final Answer
The crystal system having rectangular prisms is **Rhombic**.

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