A person with unknown blood group under ABO system, has suffered much loss in an accident and needs immediate blood trasfusion. His one friend who has a valid certifacte of his own blood type. What would have been the type of blood group of the donor friend

Options

A. Type B
B. Type AB
C. Type O
D. Type A

Answer

To determine the type of blood group of the donor friend who can donate blood to a person with an unknown blood group, we can follow these steps:

### Step 1: Understand the ABO Blood Group System
The ABO blood group system consists of four main blood types: A, B, AB, and O. Each blood type is defined by the presence or absence of specific antigens (A and B) on the surface of red blood cells.

### Step 2: Identify the Universal Donor
Among the four blood types, blood group O is known as the universal donor. This means that individuals with blood type O can donate blood to anyone, regardless of the recipient's blood type. This is because blood group O lacks both A and B antigens, which prevents agglutination (clumping) when mixed with other blood types.

### Step 3: Consider the Situation
In the scenario presented, the person in need of a blood transfusion has an unknown blood group. Since the blood type is unknown, it is crucial to ensure that the donor's blood will not cause any adverse reactions.

### Step 4: Conclusion
Given that blood group O is the universal donor and does not cause agglutination with any blood type, the donor friend must have blood type O. Therefore, the correct answer is that the donor friend has blood group O.

### Final Answer
The type of blood group of the donor friend is **Type O**.

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