Answer
$a.$ $D,E$
$b.$ $A,B,C$
$c.$ $B,A,C,E,D$
Work Step by Step
$a.$ The slope is negative at those points where the function decreases which is from graph $D$ and $E$.
$b.$ The slope is positive where the function increases which is at $A,B$ and $C$.
$c.$ We will list the points from the steepest upwards slope to the steepest downwards slope which is $B,A,C,E,D$
