Problem 23. (3.5 points) Which of the following is an equation of the line tangent to the graph of f(x) = 1 - r' at the point where f'(r) = -1 ? O (a) y= -x - 1.031 O (b) y= -1-0.836 O (c) y= -1 +0.836 O (d) y = -1 +0.934 O (e) y = -r+1.031