Answer:
A) -1/2
Explanation:
the slope is defined by the ratio of y/x.
that means that for a change of a certain number of units in x, y changes this number of units.
e.g. a slope of 5/3 means, if x changes by 3 units, y changes by 5.
the graphic shows a line that goes "down" with increasing x.
that means the slope is negative.
that eliminates C and D.
and we see that when x increases by 2 units, y decreases by 1 unit.
that means the slope is -1/2.