Human immunodeficiency virus (HIV) and Hepatitis C (HCV) are the two more prominent concerns for medical staff and for the worldwide community. Despite precautions, these diseases are both considered emerging infections. Neither of them have had vaccines developed that are effective at preventing the contraction of the disease.

reflection is the bouncing back of a propagating wave when it encounters a barrier; usually shows an image of the source of light wave

1) bounces back from an opaque material

2) bounces back from the boundary

3) seen in mirrors

refraction is the bending of a propagating wave having a shift of direction as it passes through different media; usually seen in lenses to magnify or lessen

1) passes through a prism

2) moves from one medium to another

3) seen in lenses

the answer is not right