Task: Text Categorization
Input (English): Question: Why does carbenicillin have a low antibacterial activity by mouth ?: 
 Options:  <0> It is degraded by beta-lactamases in the digestive system. <1> He undergoes first-pass hepatic oxidative metabolism. <2> It binds covalently to plasma proteins. <3> It is decarboxylated in the acid medium of the stomach giving rise to benzylpenicillin, which is also unstable in that medium. <4> It is highly lipophilic, which is why it is not released correctly from oral administration forms.
Output (English): pharmacology