Condition necessary for the formation of organ system :

Options

A. presence of all four basic type of tissue
B. Chemical interaction
C. Physical interaction
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Organ Systems**: Organ systems are complex structures formed by the integration of various organs that work together to perform specific functions in an organism.

2. **Identifying Basic Tissue Types**: There are four basic types of tissues in animals that are essential for the formation of organ systems:
- **Epithelial Tissue**: This tissue forms the lining of organs and body cavities, providing protection and facilitating absorption and secretion.
- **Connective Tissue**: This tissue supports, binds, and protects other tissues and organs; it includes bone, blood, and adipose tissue.
- **Muscular Tissue**: This tissue is responsible for movement. It can be voluntary (skeletal muscle) or involuntary (smooth and cardiac muscle).
- **Nervous Tissue**: This tissue transmits impulses and processes information, playing a crucial role in coordinating bodily functions.

3. **Conditions for Organ System Formation**: For an organ system to form, it is essential to have all four types of tissues present. Each type of tissue contributes to the structure and function of the organs within the system.

4. **Evaluating Other Options**:
- **Chemical Interaction**: While chemical interactions occur at various organizational levels (cellular, tissue, organ), they are not a prerequisite for organ system formation.
- **Physical Interaction**: Similar to chemical interactions, physical interactions are present at multiple levels of organization but do not solely determine the formation of organ systems.

5. **Conclusion**: The presence of all four basic types of tissue is the fundamental condition necessary for the formation of an organ system. Therefore, the correct answer is **Option A: Presence of all four basic types of tissue**.

---