Group member roles that reduce group success are:
a. ego tripper, negative artist
b. above it all, aggressor
c. jokester, avoider
d. all of the above (e) none of the above

Group member roles that reduce group success are ego tripper, negative artist, aggressor, jokester, avoider and that means all of these qualities can be detrimental for a group. The correct option among all the options that are given in the question is option "d" or the fourth option. These qualities can be the reason behind the failure of a team.

Group member roles that reduce group success are all of the above - D

The reason for this is the fact that having people with these group roles in a group greatly diminishes the effectiveness of the group and how it operates. 

Ithink it's a, but i might be wrong