Which of these is not an effective way to gauge the level at which your body is working during exercise
perspiration
talk test
heart rate
thirst

Heart rate is a constant usebin the medical field so the logical answer would be talk test .your talk wouldn't be impaired if you where working out.andyour thirst would play a major factor if you where working out as a factor of your perspiration.(please rate my answer so I can better understand if my reasoning where right or wrong

Cis the most source of vitamins