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: Medicine
Which is true about phage DNA 
Select and explain. 
A. Antibiotic susceptibility, B. Restriction enzyme sites, C. Hexagonal DNA, D. Carries sho segment of DNA
B: Restriction enzyme sites
Answer: B: Restriction enzyme sites 
Explanation: B i.e. Restriction enzyme sites Bacteriophage (or phages) are viruses that infect bacteria and play an impoant role in gene transfer between bacteria by mechanism of transduction that confer antibiotic resistanceQ. They usually have linear DNA moleculeQ into which foreign DNA can be inseed at several restriction enzyme sitesQ. It can carry 10- 20 kb long DNA segment(2.