$\begin{array}{l}\text{If the CP of 1 chair is Rs }x\text{, then CP of}\\ \text{1 table= Rs (}x\text{ + 210)}\\ \\ \therefore \text{ 5}x\text{+3(}x\text{\hspace{0.17em}+\hspace{0.17em}210)=3110}\\ \\ \Rightarrow \text{ 5}x\text{ + 3}x\text{ + 630 = 3110}\\ \\ \Rightarrow \text{ 8}x\text{ = 3110}-\text{630 = 2480}\\ \\ \therefore x=\frac{2480}{8}=310\\ \\ \text{:. CP of two tables and two chairs}\\ \\ \text{= 2(}x\text{ + }x\text{ + 210)= 4}x\text{ + 420}\\ \\ \text{=4}\times \text{310+ 420= Rs1660.}\end{array}$

Hence, option A is correct.