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: Biochemistry
At the physiological pH the DNA molecules are : 
Select and explain. 
A. Positively charged, B. Negatively charged., C. Neutral., D. Amphipathic
B: Negatively charged.
Answer: B: Negatively charged. 
Explanation: B i.e. Negatively ChargedDNA molecules are negatively chargedQ, this is evident as it is stained by a cationic dye (Methylene blue).