Final answer:
Santiago's book in 'The Alchemist' is used for reading, as a pillow, and as a reminder of his past as a seminarian, which best supports option D.
Step-by-step explanation:
The correct answer to the question, "Which of the following uses for Santiago's book are best supported by the novel?" is D. reading, a pillow, and a reminder of his past as a seminarian.
In 'The Alchemist' by Paulo Coelho, Santiago, the protagonist, carries a book that serves multiple purposes. He uses the book primarily for reading, but also as a pillow when resting and as a reminder of his past life before embarking on his journey to find his Personal Legend. These uses reflect Santiago's adaptation to his circumstances as a traveler and highlight his link to a life that he has left behind.