The best way to lose weight is by
performing flexibility exercises
performing cardiovascular exercises
performing muscle specificity exercises
performing resistance training exercises

The best way to lose weight is by performing cardiovascular exercises

Explanation:

Cardio is the most effective way for a person to lose weight because of the following reasons:

You are able to burn more calories, since cardio boosts your heart rate, which means your blood is pumping at a faster rate, which makes you breathe harder, and eventually you start to sweat. You can easily increase the intensity of your workout without the fear of over- training or muscle damage.

i think the answer is d.