The `RNA` which takes part in the synthesis of proteins is:

Options

A. `m-RNA`
B. `r-RNA`
C. `t-RNA`
D. All the above

Answer

To solve the question regarding which type of RNA takes part in the synthesis of proteins, we can break it down step by step:

### Step 1: Understand the Types of RNA
There are three main types of RNA involved in protein synthesis:
1. **mRNA (messenger RNA)** - This RNA carries the genetic information from DNA to the ribosome, where proteins are synthesized.
2. **rRNA (ribosomal RNA)** - This RNA forms the core of the ribosome's structure and catalyzes protein synthesis.
3. **tRNA (transfer RNA)** - This RNA brings the appropriate amino acids to the ribosome during protein synthesis.

### Step 2: Analyze the Role of Each RNA Type
- **mRNA**: It serves as a template for the sequence of amino acids in a protein. It is synthesized from DNA and carries the code needed for protein synthesis.
- **rRNA**: It is a structural component of ribosomes, which are the sites of protein synthesis. It helps in the assembly of amino acids into proteins.
- **tRNA**: It transports specific amino acids to the ribosome, matching them to the coded message in mRNA.

### Step 3: Conclusion on Protein Synthesis
Since all three types of RNA (mRNA, rRNA, and tRNA) play essential roles in the process of protein synthesis, we can conclude that the correct answer to the question is:

**All of the above (Option 4)**

### Final Answer
The RNA which takes part in the synthesis of proteins is: **All of the above (Option 4)**.

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