The differentiable function g is defined for all real numbers, and g′(5) exists. Which of the following difference quotients is most likely to give the best numerical approximation of g′(5)?
a) 0.2g(5.1)−g(4.9)
b) 0.001g(5.001)−g(5)
c) 1g(6)−g(5)
d) 1g(5)−g(4)