Histology is study of

Options

A. Tissues
B. Cells
C. Structure discernible with naked eyes
D. Changes in form and structure during development.

Answer

**Step-by-Step Solution:**

1. **Understanding Histology**: Histology is a branch of biology that focuses on the microscopic structure of tissues. It involves examining the organization and function of cells within tissues.

2. **Analyzing Options**:
- **Option 1: Tissues** - This option is correct as histology specifically studies tissues.
- **Option 2: Cells** - This option is incorrect. The study of cells is known as cytology, not histology.
- **Option 3: Structures visible to the naked eye** - This option is also incorrect. The study of structures that can be seen without a microscope is referred to as morphology.
- **Option 4: Changes during development** - This option is incorrect as well. The study of changes in form and structure during development is known as developmental biology.

3. **Conclusion**: After evaluating all the options, the correct answer is that histology is the study of tissues.

**Final Answer**: Histology is the study of tissues.

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