Why would a clone be a good source for a

blood, organ, or bone marrow transplant?

cloning is a source of tissue fr transplantation

Explanation:

this process could be used to produce organs or other parts and it has no risk of rejection when transplanted.

A clone would be an exact copy of the original organism, meaning that it would have the same blood type, same marrow, and have the same organs as the original, therefore putting possible organ/blood/marrow transplant rejection much less likely than to have a different organism donor.