Final answer:
A smaller ratio indicates a higher percentage of vasoconstrictor in the anesthetic agent, which is used to prolong the effect of the anesthetic and reduce bleeding.
Step-by-step explanation:
The correct answer to the question is B) smaller. In the context of anesthetic agents, a smaller ratio typically indicates a higher concentration of vasoconstrictor. Vasoconstrictors are added to local anesthetics to constrict blood vessels, which slows down the absorption of the anesthetic, prolonging its effect and reducing bleeding in the area. An example of such a vasoconstrictor that is commonly used is epinephrine. So when you encounter a smaller ratio of local anesthetic to vasoconstrictor, it means there is a relatively higher percentage of the vasoconstrictor present.