Answer:
The correct option is A.
Explanation:
The slope intercept form of a line is
.... (1)
where, m is slope and b is y-intercept.
The equation of Function A is
.... (2)
From (1) and (2) we get

It means slope of Function A is 1.
If a line passes through two points
and
, then slope of the line is

From the given graph it is clear that the line passes through two points (0,-1) and (1,1).

The slope of Function B is 2.
We can say that
Slope of Function B = 2 x Slope of Function A
Therefore the correct option is A.