The cauliflower mosaic virus particles contain

Cauliflower Mosaic Virus (CaMV) is a type of virus that can infect cauliflower plants and cause diseases.
Viruses are very small infectious agents. They are different from bacteria or fungi. A key difference is what they use to store their genetic information.
Genetic information is like a set of instructions telling the virus how to reproduce. Some viruses use DNA for these instructions, while others use RNA.
CaMV is unique because it uses DNA to store its genetic instructions. It doesn't use RNA.
Therefore, the correct answer is A: DNA.