Adapater molecule is

Options

A. mRNA
B. rRNA
C. DNA
D. tRNA

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the "adapter molecule" in the context of molecular biology.

2. **Identifying the Options**: The options provided are:
- a) mRNA (messenger RNA)
- b) rRNA (ribosomal RNA)
- c) DNA
- d) tRNA (transfer RNA)

3. **Analyzing Each Option**:
- **mRNA**: This molecule is synthesized from DNA during transcription and carries the genetic information to the ribosome for protein synthesis. However, it does not serve as an adapter.
- **rRNA**: This is a component of ribosomes and plays a structural role in protein synthesis but does not act as an adapter.
- **DNA**: This molecule contains the genetic blueprint for an organism but does not function as an adapter in translation.
- **tRNA**: This molecule is crucial in translation as it carries amino acids to the ribosome and matches them to the codons on the mRNA. It has an anticodon that pairs with the mRNA codon, which is why it is referred to as an adapter molecule.

4. **Conclusion**: Based on the analysis, the correct answer is **d) tRNA (transfer RNA)**, as it acts as the adapter molecule that facilitates the translation of mRNA into proteins.

### Final Answer:
The adapter molecule is **transfer RNA (tRNA)**.

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