This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
Isoantigens are - 
Select and explain. 
A. Found in some but not all members of species, B. Found in some but not all members of species, C. Occurs in different biological species, class and kingdoms, D. All individuals in a paicular species
B: Found in some but not all members of species
Answer: B: Found in some but not all members of species 
Explanation: Isoantigens are antigens found in some but not all members of a species. A species may be grouped depending on the presence of different isoantigens in its members. The best example is human erythrocyte antigens, based on which individuals can be classified into different blood groups. Reference:athanarayan & paniker's 9th edition, pg no: 89 <\p>