Molecular probes used for identification of recombinant clone carrying the desired DNA insert can be
A. denatured double stranded DNA probes
B. double stranded RNA probes
C. protein probes
D. single stranded DNA probes.

Options

A. A, B
B. B, C
C. A, D
D. A, B, C, D

Answer

To determine the correct type of molecular probe used for the identification of recombinant clones carrying the desired DNA insert, we can analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Molecular Probes**: Molecular probes are used to detect specific sequences of nucleic acids (DNA or RNA) in a sample. They are crucial in identifying recombinant clones that contain a desired DNA insert.

2. **Analyzing Option A - Denatured Double-Stranded DNA Probes**:
- Denatured double-stranded DNA probes are created by heating double-stranded DNA to separate the strands. This results in single-stranded DNA that can hybridize with complementary sequences in the target DNA.
- **Conclusion**: This option is valid because denatured DNA probes can effectively bind to complementary DNA sequences.

3. **Analyzing Option B - Double-Stranded RNA Probes**:
- Double-stranded RNA probes are less commonly used for DNA identification. They are more relevant in detecting RNA sequences rather than DNA inserts.
- **Conclusion**: This option is not suitable for identifying recombinant DNA clones.

4. **Analyzing Option C - Protein Probes**:
- Protein probes are used to detect proteins rather than nucleic acids. They do not hybridize with DNA or RNA.
- **Conclusion**: This option is not appropriate for the identification of DNA inserts.

5. **Analyzing Option D - Single-Stranded DNA Probes**:
- Single-stranded DNA probes can hybridize with complementary DNA sequences, making them effective for identifying specific DNA inserts in recombinant clones.
- **Conclusion**: This option is valid as well.

6. **Final Decision**:
- Both Option A (Denatured double-stranded DNA probes) and Option D (Single-stranded DNA probes) are suitable for identifying recombinant clones carrying the desired DNA insert. However, the most commonly used probes in this context are single-stranded DNA probes.

### Answer:
The correct answer is **D. single stranded DNA probes**.