Table 151 Shows the ID₅₀ for Staphylococcus Aureus in Wounds with Bacterium

Multiple Choice

$\begin{array} { l | l | l } \text { Bacterium } & \text { Portal of Entry } & \text { ID50 } \\\hline \text { Stephylococcus aureus } & \text { Wound } & < 10 \\\hline \text { Stephylococcus aureus } & \text { Wound + Ampicillin } & 300\end{array}$ Table 15.1 shows the ID₅₀ for Staphylococcus aureus in wounds with and without the administration of ampicillin before surgery. Based on the data, the administration of ampicillin before surgery

A) increases the risk of staphylococcal infection.
B) decreases the risk of staphylococcal infection.
C) replaces tetracycline.
D) has no effect on risk of infection.
E) The answer cannot be determined based on the information provided.