Find the critical points of the following function. Use the Second Derivative Test to determine (if possible) whether each critical point corresponds to a local maximum, a local minimum, or a saddle point. If the Second Derivative Test is inconclusive, determine the behavior of the function at the critical points. f(x,y) = 4+2x4+64 Use the Second Derivative Test to find the saddle points. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. The test shows that the saddle point(s) is/are at (Type an ordered pair. Use a comma to separate answers as needed.) B. The test does not reveal any saddle points and there are no critical points for which the test is inconclusive, so there are no saddle points. O C. The test does not reveal any saddle points, but there is at least one critical point for which the test is inconclusive. Determine the behavior of the function at any of the critical points for which the Second Derivative Test is inconclusive. Select the correct choice below and, if necessary, fill in the answer box(es) to complete your choice. (Type an ordered pair. Use a comma to separate answers as needed.) O A. Among these points, there are local maximum/maxima at , local minimum/minima at . and saddle point(s) at O B. Among these points, there are local maximum/maxima at . no local minima, and no saddle points