Answer: Interest group
Step-by-step explanation:
Interest group is the collection of members that get together for sharing common concern, topic or subject for impacting the policy to work towards their own cause. They expect policy to benefit the interest group that have similar concept of thought.
According to the situation mentioned in question,Barb wants to form the task group so that she can receive different opinions and ideas from the members of the group on her novel rather than forming interest group with common share of thoughts which will not let her receive new ideas..