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: Microbiology
Ideal percentage of CO2 required for growth of Brucella abous ? 
Select and explain. 
A. 2-5%, B. 5-10%, C. 15-20%, D. 25-30%
B: 5-10%
Answer: B: 5-10% 
Explanation: Ans. is. b. i.e., 5-10% "Addition of 5-10% CO, improves the growth of B abous and B. melitensis".All Brucella spp. are strictly aerobic, but some B. abous biovars, some Brucella isolates from marine mammals, and B. ovis only grow in atmospheres containing 5-10% CO,.