किस नदी को छत्तीसगढ़ राज्य की 'जीवन रेखा' कहा जाता है?

Which of the following territories was annexed by Lord Dalhousie under the pretext of misgovernance, and not directly through the Doctrine of Lapse?

What was the primary stated reason for the Partition of Bengal in 1905 by Lord Curzon?