This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
All are true about ciprofloxacin except ? 
Select and explain. 
A. C/I in pregnancy, B. DNA inhibition, C. Most potent 1st generation fluoroquinolone, D. More active at acidic pH
D: More active at acidic pH
Answer: D: More active at acidic pH 
Explanation: Ans. is 'd' i.e., More active at acidic pH Ciprofloxacin is the most potent first generation FQ. o Ciprofloxacin inhibit DNA gyrase and is contraindicated in pregnancy. It is less active at acidic pH.