Determine where the given function is concave up and where it is concave down. G(X) = X + 6 O A. Concave up for ( - co, 0), concave down for (0, co) O B. Concave up for (2, co), concave down on ( - co, 2) O C. Concave up on (0, 2), concave down on ( - co, 0) and (2, co) O D. Concave up on ( - co, 0) and (2, co), concave down on (0, 2)