To prepare for a group discussion on his own, it would be best for Tomas to begin by working with the group to establish roles.
establishing the discussion’s goals.
setting the rules for the discussion.
researching the topic.

D.   researching the topic.

Explanation:

The question says what would be best for Tomas to do on his own and the answer to that is to research the topic.

b. africa to the americas

explanation:

the catholic church withhold people's access to the bible during the middle ages.

people could go to church and listen to the teachings, but it was absolutely forbidden to own and/or read the books of both the old and new testaments. it was also prohibited to translate the books (which where originally in biblical hebrew) to any other language.

this was done so the church could remain in control of what their teachings were and to enhance their importance and power, while also being able to judge people's actions through information that was unavailable for the general public.