There are types of roles in group work.
a. 2
b. 5
c. 3
d. 6

There are 3 types of roles in group work. (Option C) These types are: task role, maintenance role, and hindering role.

Firstly, the task role refers to the initiation, clarifying, as well as summarization of the work.

Secondly, the maintenance role is the encouragement and setting the standards for the team and the work.

Finally, the hindering role refers to any action of each individual of the team that hinders the process of finishing the project.

i'm sorry i don't understand the question.

not concrete, existing in thought or as an idea but not having a physical or concrete existence