Consider the following reaction \(\mathrm{A}+\mathrm{B} \rightarrow \mathrm{C}\) The time taken for \(A\) to become \(1 / 4^{\text {th }}\) of its inital concentration is twice the time taken to become \(1 / 2\) of the same. Also, when the change of concentration of \(B\) is plotted against time, the resulting graph gives a straight line with a negative slope and a positive intercept on the concentration axis. The overall order of the reaction is _______.

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.