Most of the mutations are lethal ad may lead to death of organism.

Answer

### Step-by-Step Solution:

1. **Understanding Mutations**:
- Mutations are defined as small genetic changes that occur in the DNA sequence of an organism. These changes can affect how genes function and can be passed down to future generations.

2. **Nature of Mutations**:
- Mutations can be classified into different types, including beneficial, neutral, and harmful mutations. While it is true that many mutations can be lethal, not all mutations lead to death.

3. **Impact of Mutations**:
- The impact of a mutation can vary. There is a 50% chance that a mutation may lead to the formation of a new allele, which can contribute to the process of evolution. This can be beneficial for the species in adapting to changing environments.

4. **Lethal Mutations**:
- On the other hand, there is also a 50% chance that a mutation can result in harmful or lethal effects. These mutations can disrupt essential biological functions, leading to the death of the organism.

5. **Conclusion on the Statement**:
- The statement that "most mutations are lethal" is misleading. While lethal mutations do occur, they do not account for the majority of all mutations. Many mutations can be neutral or even beneficial, contributing to genetic diversity and evolution.

### Final Statement:
In summary, while many mutations can be lethal and lead to the death of an organism, it is inaccurate to claim that most mutations are lethal. Mutations can also promote evolution and genetic diversity.

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