Final answer:
The student nurse's best response is that co-infection with C. trachomatis is common in patients with gonorrhea, so the two-drug treatment regimen is used to cover both infections.
Step-by-step explanation:
The student nurse's best response is b) "Many people infected with gonorrhea are infected with chlamydia as well."
Co-infection with C. trachomatis is common in patients with gonorrhea. Since testing to distinguish between the two infections may not be available, the CDC recommends a two-drug treatment regimen that covers both infections. In this case, the patient is receiving ceftriaxone and doxycycline to treat both gonorrhea and chlamydia.
By using two antibiotics, the treatment can address the possibility of co-infection and ensure the patient receives effective treatment for both infections.