Correct Option: C **Step-by-step Breakdown:** **Objective:** To determine the total quantity of the mixture. Let D be the quantity of Darjeeling tea and A be the quantity of Assam tea. The total quantity of the mixture is \(T = D + A\). **Analyzing Statement I:** * Statement I states: The quantity of Darjeeling tea used in the mixture was 60 kg. * This provides us with \(D = 60\) kg. * We still do not know the quantity of Assam tea (A), nor do we know the proportion of Darjeeling tea in the mixture. * Therefore, we cannot determine the total quantity \(T\) from Statement I alone. * **Conclusion:** Statement I alone is not sufficient. **Analyzing Statement II:** * Statement II states: The Darjeeling tea constituted 60% of the total mixture by weight. * This can be expressed as: \(D = 0.60 \times T\) or \(D = \frac{60}{100} \times T\) or \(D = \frac{3}{5} \times T\). * This statement provides a relationship between the quantity of Darjeeling tea and the total quantity, but we do not know the absolute value of either \(D\) or \(T\). * Therefore, we cannot determine the total quantity \(T\) from Statement II alone. * **Conclusion:** Statement II alone is not sufficient. **Analyzing Statements I and II together:** * From Statement I, we have \(D = 60\) kg. * From Statement II, we have \(D = 0.60 \times T\). * Substitute the value of \(D\) from Statement I into the equation from Statement II: \(60 = 0.60 \times T\) * To find \(T\), we can rearrange the equation: \(T = \frac{60}{0.60}\) \(T = \frac{60}{\frac{6}{10}}\) \(T = 60 \times \frac{10}{6}\) \(T = 10 \times 10\) \(T = 100\) kg * We can uniquely determine the total quantity of the mixture as 100 kg. * **Conclusion:** Both Statements I and II together are sufficient. Since neither statement alone is sufficient, but both statements together are sufficient, the correct option is C.