Presence of long neck and high forelimbs in giraffe can be best explained by:

Options

A. Lamarckism
B. Neodarwinism
C. Neolamarckism
D. Bottleneck effect

Answer

To answer the question regarding the presence of long neck and high forelimbs in giraffes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the explanation of the long neck and high forelimbs in giraffes, which are adaptations that have evolved over time.

2. **Introduction to Theories of Evolution**: There are several theories of evolution, but the question specifically hints at one that involves the inheritance of traits acquired during an organism's lifetime.

3. **Lamarckism Overview**: The theory that best explains the giraffe's adaptations is Lamarckism, proposed by Jean-Baptiste Lamarck. This theory suggests that organisms can pass on characteristics acquired during their lifetime to their offspring.

4. **Historical Context of Giraffes**: The ancestors of modern giraffes had shorter necks and limbs. They lived in environments where vegetation was high, which necessitated reaching for food that was out of their natural reach.

5. **Acquired Traits**: According to Lamarck, as these ancestors stretched their necks and limbs to reach higher vegetation, these traits were acquired during their lifetimes. Over generations, these acquired traits became more pronounced.

6. **Transmission of Traits**: Lamarck proposed that these acquired characteristics (long neck and high forelimbs) were then inherited by the next generation, leading to the evolution of the modern giraffe with its distinctive long neck and limbs.

7. **Conclusion**: Therefore, the presence of long neck and high forelimbs in giraffes can be best explained by Lamarckism, which emphasizes the inheritance of acquired characteristics.

### Final Answer:
The presence of long neck and high forelimbs in giraffes can be best explained by **Lamarckism**, which is the theory of inheritance of acquired characters.

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