What can be achieved/ can be prevented?
Proper checking of blood before blood donation.

Hint: Blood donation is linked to blood transfusion and blood types. Blood is given to someone who is in need of it. It's done by determining a person's blood types and then transfusing the appropriate blood group into them.
Precautions while blood transfusion-
Donors must be in good health and free of disorders such as sexually transmitted diseases, viruses such as hepatitis, and so on.
A compatible blood transfusion is required.
Blood transfusions should be done slowly to avoid putting too much strain on the heart.
Blood transfusions should not be performed using improper techniques, since this could result in adverse reactions.

Complete answer:
The purpose of blood donation is to save a person's life. It is accomplished by the procedure of blood transfusion, which involves the transfer of blood from one person (donor) to another person (recipient) (receipnt). It's also referred to as a life-saving surgery.
Before donating blood, proper testing is essential to ensure that the blood being transmitted is safe in every way. To begin, the donor and recipient's blood groups must be compatible. Second, if the donor has any infectious disorders, there is a potential that they will be passed on to the recipient. Another crucial aspect of blood testing prior to donation is to ensure that the donor is not anaemic (does not have anemia).
When transfusing blood, the donor's antigen and the recipient's antibody are taken into account.
Because blood group O has no antigen, it is said to be a universal donor because agglutination does not occur with any other blood group. The blood group AB is known as a universal recipient because its plasma has no antibodies that trigger agglutination.

Note:
When blood is lost as a result of accidents or surgeries, blood donation is required. It's particularly crucial when anaemia, haemorrhage, or trauma, such as burns, necessitates regular blood transfusions. If blood is supplied at the correct time, many single lives can be spared.
Antigen and antibody for blood categorization are two different forms of glycoproteins.
Agglutination is the process of combining antigen and antibody to create a response.
There is no better deed than blood donation because it saves a valuable human life. Many people die as a result of a lack of blood. As a result, healthy individuals, regardless of caste, creed, or race, donate blood so that human lives can be saved in a timely manner.