I believe the answer is D
Answer:
Vaccines have been around since 1796 preventing people from diseases and decreasing death rates. I believe due to the modern vaccines and medicine people have been living longer than life expectancies in the 1700's and 1800’s, which was between 30 and 40 years. Vaccines train the human body to recognize viruses or bacteria and the antigens (molecule capable of inducing an immune response) will start attacking the virus or bacteria before it tries to spread and cause sickness once it is has recognized it. However, vaccines are not always 100% safe because they can come with side effects. For example, the Hepatitis B vaccine had a severe allergic reaction, called anaphylaxis which caused difficulty breathing, dizziness, and skin rashes for a few people.
Answer:
Pubic Lice and Scabies are different than previously mentioned STDs in that they are caused by an infestation of small bugs rather than by bacteria. Pubic lice are six-legged creatures known in the scientific world as Phthirus Pubis and more commonly as "crabs".
Explanation:
hope that helps you. :)