Depends on what you mean by cold.
If you mean like cold, like tempurature, then wear the smallest amount of cloths, and use air conditioning.
A) they allow an athlete to exercise longer
(i just took the quiz)
Viral infections cannot be treated with antibiotics. They can only be treated with antivirals. That is why u go to the doctor and they say it's viral and it has to run its course. If you get to ill they may give prophylactic antibiotics to prevent secondary infection while your body is fighting off the virus
B) Vaginal
Vaginal is always the best option, all these others have a higher risk of damage to the internal glands.