2. Which types of blood have the antigens that will react with anti-A antibodies?

A will react as well as AB. There could be more but thats the ones I know of.

They are of blood groups A and group AB.

Explanation:

The anti-A serum would cause blood containing red blood cells with antigen A to clump, while in the other antigen which is B serum would cause blood containing red blood cells with antigen B to clump. The clumping of red blood cells is called agglutination. Aside antigens A and B, red blood cells also contain another antigen called the Rhesus factor.

A simple agglutination test using an anti-Rhesus serum can identify if our blood is Rhesus positive ornRhesus negative.