A：$\frac{x^2}{16}+\frac{y^2}{12}=1$

B：$\frac{x^2}{12}+\frac{y^2}{16}=1$

C：$\frac{x^2}{16}+\frac{y^2}{4}=1$

D：$\frac{x^2}{4}+\frac{y^2}{16}=1$