Why are crystalline solids anisotropic ?

Explanation

**Step-by-Step Solution:**

1. **Definition of Crystalline Solids:**
Crystalline solids are materials whose constituents (atoms, ions, or molecules) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

2. **Understanding Anisotropy:**
Anisotropy refers to the directional dependence of a material's properties. In contrast, isotropic materials have properties that are the same in all directions.

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