The modern cell theory

Options

A. Protoplsmic Theory
B. Cell Principle
C. Cell Doctrine
D. Both B and C

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the modern cell theory and its components. We need to identify the correct options that relate to the modern cell theory.

2. **Identifying the Theories**:
- **Protoplasmic Theory**: This theory suggests that protoplasm is the physical basis of life, introduced by scientist Huxley. However, it is not a part of the modern cell theory.
- **Cell Principle**: This principle states that all cells are the structural and functional units of life and that they arise from pre-existing cells. This is a key component of the modern cell theory.
- **Cell Doctrine (or Cell Theory)**: This states that all organisms are composed of similar units of organization, which is also a fundamental aspect of the modern cell theory.

3. **Analyzing the Options**:
- Option A (Protoplasmic Theory) is not part of the modern cell theory.
- Option B (Cell Principle) is correct as it aligns with the modern cell theory.
- Option C (Cell Doctrine) is also correct as it is part of the modern cell theory.
- Option D (Both B and C) is correct because both the Cell Principle and Cell Doctrine are integral to the modern cell theory.

4. **Conclusion**: Since options B and C are both correct and represent key components of the modern cell theory, the correct answer is option D (Both B and C).

**Final Answer**: D (Both B and C)

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