The answer is; E. It proposes that people have emotional reactions to the failure or success of their group because their self-esteem is tied into the group's performance.
According to social identity theory, people will form a sense of 'who they are' depending on the social group where they belong/identified with.
This make people feel the social group as the extension of themselves. They will feel negative emotional reason when the group suffer and will feel otherwise if the group succeed.
For example, pay attention to sport fans. Let's say Tony is a die hard Red-Sox fans. He went to almost all red-sox games with his friends even when the red-sox hasn't won any title for a long time. When they do, People who identified as a part of hardcore red-sox fandom would most likely experience a large amount of joy if the red-sox manage to win the championship.