Which blood type can be transfused into a patient who has blood type A-?

For a person with blood type A - (A negative), they can be transfused with either blood type A negative, or blood type O negative.

This is because any other blood type will immediately be rejected by their body.

A person with blood type A negative has got antibodies against any other blood type which has a rhesus positive factor as well as antibodies against any other blood type of a different group such as B and AB, even if they are rhesus negative.

Therefore because of the rhesus negative factor, a person with blood type A negative can only be transfused with rhesus negative.