An Antibiotic Is Given Repeatedly to Treat a Recurrent Ear

question 63

Multiple Choice

An antibiotic is given repeatedly to treat a recurrent ear infection. It worked initially but now is no longer effective. This indicates that the Streptococcus bacterium

• A) is being treated with an antibiotic that has experienced a manufacturing error, making it infective.
• B) is very sensitive to the antibiotic.
• C) is infectious only if it is sensitive to the antibiotic.
• D) experienced natural selection that has allowed the resistant Streptococcus to survive and multiply.

---

Definitions:

Methyl Ester

Organic compounds formed from the reaction of an acid with methanol, characterized by a methyl group attached to the ester functional group.

Carboxylic Acid

Organic acids characterized by the presence of at least one carboxyl group (-COOH), which gives them their acidic properties.

Hell-Volhard-Zelinsky

A chemical reaction that halogenates carboxylic acids at the alpha carbon with a bromine or chlorine in the presence of phosphorus.

Organic Product

A compound or material derived from living organisms, or synthetically produced to mimic such substances.