A Dietitian Is Asked to Design a Special Dietary Supplement $$\left\{ \begin{array} { c } 20 x + 10 y \geq 350 \\15 x + 10 y \geq 300 \\10 x + 20 y \geq 400 \\x \geq 0 \\y \geq 0\end{array} \right.$$

A dietitian is asked to design a special dietary supplement using two different foods.Each ounce of food X contains 20 units of calcium,15 units of iron,and 10 units of vitamin B.Each ounce of food Y contains 10 units of calcium,10 units of iron,and 20 units of vitamin B.The minimum daily requirements of the diet are 350 units of calcium,300 units of iron,and 400 units of vitamin B.Write a system of inequalities describing the different amounts of food X and food Y that can be used. ​

A) $$\left\{ \begin{array} { c } 20 x + 10 y \geq 350 \\15 x + 10 y \geq 300 \\10 x + 20 y \geq 400 \\x \geq 0 \\y \geq 0\end{array} \right.$$
B) $$\left\{ \begin{array} { c } 20 x + 10 y \geq 400 \\15 x + 10 y \geq 350 \\10 x + 20 y \geq 300 \\x \geq 0 \\y \geq 0\end{array} \right.$$
C) $$\left\{ \begin{array} { c } 20 x + 10 y \geq 300 \\15 x + 10 y \geq 350 \\10 x + 20 y \geq 400 \\x \geq 0 \\y \geq 0\end{array} \right.$$
D) $$\left\{ \begin{array} { c } 20 x + 10 y \geq 400 \\15 x + 10 y \geq 300 \\10 x + 20 y \geq 350 \\x \geq 0 \\y \geq 0\end{array} \right.$$
E) $$\left\{ \begin{array} { c } 20 x + 10 y \geq 300 \\15 x + 10 y \geq 400 \\10 x + 20 y \geq 350 \\x \geq 0 \\y \geq 0\end{array} \right.$$