Which of the following occurs in fluid competitive systems?

a. Both geographic and social mobility are lessened in fluid competitive systems,
b. Fluid competitive systems are more closed, and the position of the minority group is more fixed.
c. In fluid competitive systems, intergroup conflict increases,
d. In fluid competitive systems, the division of labor is simple and does not vary greatly within groups,
e. In fluid competitive systems, fear of competition from minority groups diminishes.