Question

Antigen - A and Antibody - B are present in which group
A) B
B) A
C) AB
D) O

Answer 1

A foreign or toxic substance, which can induce an immune response in the body are known as antigens. Antibodies are specific proteins which are produced in response to an antigen, which can trigger an immune reaction.

Complete answer:
Before looking through the options, let's have a look at the blood group classification of the human body.
Antigens are protein molecules which are present on the surface of bacteria, fungi, red blood cells and other foreign substances. When they enter into the body, it initiates an immune response, thereby producing antibodies. The surface of red blood cells have many molecules, also called antigens, which vary in different individuals.

The blood group system is classified on the basis of antigens found on the surface of red blood cells. The ABO blood group system of the human body consists of two antigens and two antibodies. Antigen A and Antigen B are the two antigens and Antibody A and Antibody B are the two antibodies found in the body. Antigens are present in the red blood cells and antibodies are seen in the serum.
Let's have look through the options to find the correct answer:
Option B: Blood group A consists of antigen A and antibody B. Therefore, this is the correct option.
Option A, C and D: These options are irrelevant, therefore, these are the incorrect options.

Thus, the correct answer is option (B) ‘A’.

Note: A reaction called agglutination occurs between similar antigen antibodies. During blood transfusion, it is safe as long as the serum of the recipient doesn't contain the same antibodies for the blood cell antigens of the donor.