Question

One limitation of the analysing the function y= f(x_1,…,x_n) with partial derivatives only is:
a) that it only makes sense for very large changes of x_1,…,x_n.
b) that only indirect effects are taken into account
c) that it does not contemplate contemporaneous changes in the x_1,…,x_n variables
d) that it only applies to quadratic or cubic functions