No âmbito do direito do trabalho, o aviso prévio, como a própria terminologia sugere, é a necessária comunicação anterior de uma parte a outra sobre a intenção de encerrar o contrato de trabalho. trata-se de um instituto jurídico bastante importante, pois visa evitar surpresas, com necessidade de diligências repentinas ora junto ao trabalhador, ora junto ao empregador. nesse contexto, a característica peculiar do aviso prévio é:

The answer is d because , safety almost always works, to prevent stds and pregnancy

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." 

I'm pretty sure it's worms.

The answer is chope i