Answer: b. Carry on a conversation
Explanation:
There are different levels of intensity when exercising and these require different energy levels and different amounts of air coming into the lungs.
The CDC notes that if you are exercising at a moderate level, the energy and oxygen requirements will not be as high so you can be able to talk to other people without being short of breath from needing more of the oxygen and energy that is being used in the talking.
"D.all of the above" is the answer
The best possible way to verify claims a manufactures makes about a supplement's safety and effectiveness would be to go to the manufactures website and look at the reviews, research the studies behind their product and ask around. Since supplements are usually regulated by the FDA, manufacturers are basically given the "honor system" to provide accurate information to consumers. Doing your own research will help immensely. If you ever see something on a supplement(s) that says, "This statement has not been verified by the Food and Drug Administration", I would take it at my own risk.
You should be worried if the product claims a miracle cure
