Which one of the following statements is correct regarding sexually transmitted diseases (STDs)?
Syphilis is caused by bacterium Treponema pallidum. It is a sexually transmitted disease (STD) which is transmitted through sexual intercourse with infected person. Haemophilia is an X-linked genetic disorder of blood, It is not transmitted via any sexual practice. Genital herpes is an STD while sickle-cell anaemia is an autosomal hereditary disorder. The chances of a 5 years old boy contacting an STD are very rare since he is unlikely to have sex at this age. So, the correct answer is 'The chances of a 5-years boy contracting a STD are very rare'.