Choice A rationale:

Antiviral medications are not typically used to treat uncomplicated cases of measles. Supportive care is the mainstay of treatment.

Choice B rationale:

Isolating the client in a private room with negative pressure ventilation is appropriate to prevent the spread of airborne infections like tuberculosis but is not a standard precaution for measles.

Choice C rationale:

Wearing an N95 respirator mask when entering the client's room is essential because measles is highly contagious and transmitted through the respiratory route.

Choice D rationale:

Monitoring vital signs, especially temperature, pulse, and oxygen saturation, is crucial to assess for any signs of complications and to monitor the client's overall condition.

Choice E rationale:

Providing oral care to the client with Koplik spots or oral ulcers is essential for maintaining oral hygiene and preventing secondary infections.