Cloning vector contains

Options

A. DNA
B. RNA
C. DNA and RNA
D. DNA and Proteins

Answer

### Step-by-Step Text Solution:

1. **Definition of Cloning Vector**: A cloning vector is a small piece of DNA that can be maintained and replicated within a host organism. Its primary function is to carry foreign DNA fragments for the purpose of cloning.

2. **Characteristics of Cloning Vectors**:
- They must be able to replicate independently within a host.
- They should have a mechanism to insert foreign DNA.
- They need to be stably maintained in the host organism.

3. **Common Types of Cloning Vectors**: The most commonly used cloning vectors are plasmids derived from *E. coli*. These plasmids are small, circular DNA molecules that can carry additional genetic material.

4. **Components of a Cloning Vector**:
- **Origin of Replication (ori)**: This allows the vector to replicate within the host.
- **Selectable Marker Genes**: These genes help in identifying and selecting the cells that have successfully taken up the vector.
- **Multiple Cloning Site (MCS)**: This is a region containing several restriction sites where foreign DNA can be inserted.

5. **Conclusion**: Based on the characteristics and components of cloning vectors, the correct answer to the question "Cloning vector contains" is that it contains DNA.