The value of 80 - 112 45 - 63 = ?

Answer: Option C

$$\begin{array}{rl}& \text{According to the question,}\\ & \frac{\sqrt{80}-\sqrt{112}}{\sqrt{45}-\sqrt{63}}\\ & \Rightarrow \frac{4\sqrt{5}-4\sqrt{7}}{3\sqrt{5}-3\sqrt{7}}\\ & \Rightarrow \frac{4\left(\sqrt{5}-\sqrt{7}\right)}{3\left(\sqrt{5}-\sqrt{7}\right)}\\ & \Rightarrow \frac{4}{3}\\ & \Rightarrow 1\frac{1}{3}\end{array}$$