Final answer:
The agent that causes measles (rubeola) is the Measles virus (MeV), which is responsible for the characteristic symptoms and highly infectious nature of the disease.
Step-by-step explanation:
The agent that causes the highly contagious disease measles, also known as rubeola, is c. Measles virus (MeV). This is a single-stranded, negative-strand RNA virus that is enveloped with spikes of hemagglutinin. The disease spreads through direct contact with infectious secretions or by inhalation of airborne droplets from breathing, coughing, or sneezing. Measles is characterized by a high fever, conjunctivitis, a sore throat, Koplik's spots, and a red, raised macular rash that starts on the face and spreads to the extremities.