The idea not related to the Darwinian evolutionary theory is :

Options

A. survial of the best
B. struggle for existence
C. inheritance of acquired characters
D. origin of species by natural selection

Answer

To solve the question regarding which idea is not related to the Darwinian evolutionary theory, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding the Options**:
- We have four statements to evaluate:
a) Survival of the best
b) Struggle for existence
c) Inheritance of acquired characters
d) Origin of species by natural selection

2. **Analyzing Each Statement**:
- **Statement a: Survival of the best**:
- This concept aligns with Darwin's theory of natural selection, where organisms that are better adapted to their environment are more likely to survive and reproduce.

- **Statement b: Struggle for existence**:
- This is also a key component of Darwin's theory. It refers to the competition among organisms for limited resources, which is essential for natural selection.

- **Statement c: Inheritance of acquired characters**:
- This idea is not part of Darwin's theory. It was proposed by Lamarck, suggesting that traits acquired during an organism's lifetime can be passed on to its offspring. Darwin did not support this idea; he focused on natural selection and genetic inheritance.

- **Statement d: Origin of species by natural selection**:
- This statement is directly related to Darwin's work. He proposed that species evolve over time through the process of natural selection.

3. **Identifying the Incorrect Statement**:
- After analyzing all the statements, it is clear that the statement "Inheritance of acquired characters" (option c) is the one that is not related to Darwinian evolutionary theory.

### Conclusion:
The idea not related to the Darwinian evolutionary theory is **Inheritance of acquired characters** (option c).

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