What is the value of $\lim _{x \rightarrow 0 \atop y \rightarrow 0} \frac{x y}{x^{2}+y^{2}} ?$
(A) 1
(B) -1
(C) 0
(D) Limit does not exist
What is the value of $\lim _{x \rightarrow 0 \atop y \rightarrow 0} \frac{x y}{x^{2}+y^{2}} ?$
(A) 1
(B) -1
(C) 0
(D) Limit does not exist