What is the best way to lose body fat? select one:
a. crash diets
b. exercising alone
c. diet pills and supplements
d. sensible diet and regular exercise?

D, because all others could affect other parts of your health. Don't crash diets, after so long your body can go into starvation mode. Exercising alone--- if there is not another person with you, you may be tempted to over-exercise. And C is incorrect because those pose big risks to your health, depending upon the combination or even duration/side-effects.
And D is correct because you're still eating--- just maybe more healthily and exercising, but not too much or too little. 

You answer would be c.

The reason being is because  antibiotics do not work for viral infections.  i hope this ! have a great day!