The value of $$3 - 25 \div [12 \div 4 \times 2 - (3 \times 7 \div 21)]$$ is:​

Correct option is A

Given: 

​$$3 - 25 \div [12 \div 4 \times 2 - (3 \times 7 \div 21)]$$ 

Concept Used: ​

BODMAS rule;

$$\begin{array}{|c|c|} \hline \textbf{Operation preference wise} & \textbf{Symbol} \\ \hline Brackets &[],{}, () \\ \hline Orders, of & ² (power), √ (root) , of \\ \hline Division & ÷ \\ \hline Multiplication & × \\ \hline Addition & + \\ \hline Subtraction & - \\ \hline \end{array}$$ 

Solution: ​

​$$3 - 25 \div [12 \div 4 \times 2 - (3 \times 7 \div 21)] \\ \ \\ = 3 - 25 \div [12 \div 4 \times 2 - (1)]\\ \ \\ = 3 - 25 \div [5]\\ \ \\ = 3 - 5 \\ \ \\ = -2$$​​