Convenient health care clinic because insurance will cover it depending on who has your insurance.
Two answers could be correct both B and D it does depend on the type of health work you are working in if you swim you burn calories and energy so being rested is a positive answer however by many health organizations or people in general 30 minutes is a safe time to swim after digestion, but if I was to say a more accurate answer would be B
1. aerobic means "with oxygen" and anaerobic means "without oxygen"
2. aerobic can mean small exercises meaning you aren't using too much of your body's muscles and bones to workout. Anaerobic can mean big exercises meaning weight lifting.
3. With aerobic exercise the oxygen is carried through your breath to the muscles giving them the energy they needed. This is basically an example of a warm-up before an exercise. Anaerobic however makes you out of breath quickly because without doing the warm-up and you just go into the workout you are making yourself weak and not have enough energy.
Hope this helped :)
It depends on what causing it. the only thing I can say is to drink plenty of fluids but I would recommend to go see a doctor, if you are unsure or worried.