i) Sexually transmitted diseases are infections that spread by any form of sexual contact between affected individuals through the male and female genital regions of the body.

ii) Examples of sexually transmitted diseases are AIDS, syphilis etc.

iii) The measures to prevent these diseases would be to have safe sexual contact between individuals. Using condoms during intercourse, Avoid sharing of wash cloths and under garments and vaccination for some of these diseases are few of the measures that can be adopted to prevent the spread of sexually transmitted diseases.