Final answer:
The disposition of a tissue includes transplantation, discard, and distribution. However, it does not include research.
Step-by-step explanation:
The disposition of a tissue refers to what happens to it after it is removed from the body. The options listed are different ways in which tissues can be dealt with. Transplantation involves moving tissues from one person to another, discard means getting rid of the tissue, distribution involves sending the tissue to where it is needed, and research involves using the tissue for scientific studies. Therefore, the correct answer is d. Research.