What was the basic principle of Lamarckism :

Options

A. Inheritance of acquired characters
B. Survival of the fittest
C. Natural selection
D. Variations

Answer

### Step-by-Step Solution:

1. **Understanding Lamarckism**: Lamarckism is a theory of evolution proposed by Jean-Baptiste Lamarck. It emphasizes the idea that organisms can pass on traits acquired during their lifetime to their offspring.

2. **Key Concept - Inheritance of Acquired Characters**: The fundamental principle of Lamarckism is the "inheritance of acquired characters." This means that traits that an organism develops or modifies during its life due to use or disuse can be inherited by the next generation.

3. **Use and Disuse**: According to Lamarck, if an organism uses a particular organ or trait frequently, that organ will become stronger or more developed. Conversely, if an organ is not used, it may weaken or diminish. For example, if a giraffe stretches its neck to reach higher leaves, its neck may grow longer, and this trait could be passed on to its offspring.

4. **Contrast with Darwinism**: It is important to note that this principle differs from Darwin's theory of evolution, which is based on natural selection and the survival of the fittest. Darwin proposed that only those traits that confer a reproductive advantage are passed on to future generations.

5. **Conclusion**: Therefore, the basic principle of Lamarckism is the inheritance of acquired characters, which suggests that traits acquired during an organism's lifetime can be inherited by its descendants.

### Final Answer:
The basic principle of Lamarckism is the inheritance of acquired characters.

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