Consider g(x)=lnx−4x2 for x>0. Which of the following best describes the critical point of g?
a) It is a relative minimum because the graph is concave up at that point.
b) It is a relative maximum because the graph is concave down at that point.
c) It is a point of inflection where the concavity changes.
d) There is no critical point because g′(x)=0 for x>0.