Exact replication of DNA is possible due to

Options

A. genetic code
B. double helical
C. sequence of nucleotide
D. base pairing rule

Answer

To answer the question "Exact replication of DNA is possible due to," we will analyze the provided options and determine which one is correct based on our understanding of DNA replication.

### Step-by-Step Solution:

1. **Understanding DNA Replication**:
- DNA replication is the process by which a cell makes an exact copy of its DNA. This is crucial for cell division and the transmission of genetic information.

2. **Evaluating the Options**:
- The options given are:
a) Genetic code
b) Double helical structure
c) Sequence of nucleotides
d) Base pairing rule

3. **Analyzing Each Option**:
- **Genetic Code**: This refers to the set of rules that dictate how the information encoded in DNA is translated into proteins. It is not directly involved in the replication process itself. Thus, this option is incorrect.
- **Double Helical Structure**: While DNA's double helical structure is important for its stability and function, the structure itself does not directly facilitate the replication process. The DNA must unwind for replication to occur, making this option also incorrect.
- **Sequence of Nucleotides**: The sequence of nucleotides in DNA determines the genetic information. However, it does not directly explain how replication occurs. Therefore, this option is not the best answer.
- **Base Pairing Rule**: This rule states that adenine pairs with thymine (A-T) and guanine pairs with cytosine (G-C). This complementary base pairing is essential for the accurate replication of DNA, as it ensures that each new strand is an exact copy of the original strand.

4. **Conclusion**:
- The correct answer is **d) Base pairing rule**. This rule is fundamental to the exact replication of DNA, as it ensures that the new strands formed during replication are complementary to the original strands.

### Final Answer:
Exact replication of DNA is possible due to the **base pairing rule**.

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