In an effort to eat healthier foods ,you pay more attention to food label . all of the following are equired on labels,
a. serving size ,as specified by the fda
b. all ingredients, listed in descending weight
c. nutritional benefits
d. net wight of package

D, because the serving size is what matters.

Ithink it's traditional 

The answer you're looking for is washing your hands. "at this late date, we all expect our doctors to wash their hands before examining us or performing an operation in order to prevent the spread of infection. surprisingly, physicians did not begin to acknowledge the lifesaving power of this simple act until 1847.it was then that dr. semmelweis began exhorting his fellow physicians at the famed vienna general hospital (allgemeines krankenhaus) to wash up before examining women about to deliver babies. his plea was far more than aesthetic; it was a matter of life and death and to prevent a deadly malady known as “childbed” or puerperal (from the latin words for child and parent) fever."