Which virus is associated with the disease known as Cucumber mosaic?

The association of the disease known as Cucumber mosaic with the Cucumber mosaic cucumovirus is well-documented in plant pathology. Cucumber mosaic virus (CMV) is a type of RNA virus that primarily infects a wide variety of plant species, including cucumbers, melons, and various ornamental plants.

When plants are infected with this virus, they exhibit characteristic symptoms such as mottled or mosaic-patterned leaves, stunted growth, and reduced yields. This viral infection can spread rapidly within crops and between different plants, particularly through aphid vectors that facilitate its transmission.

The specificity of the name “Cucumber mosaic” directly corresponds to the symptoms and the type of virus affecting cucumbers and related plants, making it clear that the virus responsible for this disease is indeed the Cucumber mosaic cucumovirus. This direct link is what makes the correct answer aligned with the established knowledge in plant pathology. Other viruses listed in the question are associated with different diseases and plant hosts and do not cause symptoms characteristic of the Cucumber mosaic disease.