Bacteriophages are viruses that eat away bacteria. They usually have

Options

A. dsDNA
B. dsRNA
C. ssDNA
D. ssRNA

Answer

### Step-by-Step Solution:

1. **Understanding Bacteriophages**: Begin by recognizing that bacteriophages are a type of virus that specifically infects bacteria. They are often referred to as "phages."

2. **Identifying the Structure of Bacteriophages**: Bacteriophages have a unique structure that includes:
- A head (capsid) that contains the genetic material.
- A tail structure that helps in attaching to and injecting their genetic material into the bacterial host.

3. **Determining the Genetic Material**: The genetic material of bacteriophages can vary. The options provided are:
- A) Double-stranded DNA
- B) Double-stranded RNA
- C) Single-stranded DNA
- D) Single-stranded RNA

4. **Analyzing the Options**:
- Bacteriophages typically contain double-stranded DNA as their genetic material. This is a well-established fact in virology.
- Other forms of genetic material (like RNA) are not commonly associated with bacteriophages.

5. **Conclusion**: Based on the structure and the type of genetic material found in bacteriophages, the correct answer is:
- **Option A: Double-stranded DNA**.