Question

what was Doctrine of Lapse ?

Answer 1

HEY MATE HERE IS YOUR ANSWER
The doctrine of lapse was an annexation policy applied by the British East India Company in India until 1858. ... The policy is most commonly associated with Lord Dalhousie, who was the Governor General of the East India Company in India between 1848 and 1856

Answer 2

doctrine of lapse was an annexation policy applied by the east India Company in India until 1815.
this doctrine was based on the idea that in case a ruler of dependent state died childless, the right of ruling over the state reverted or 'lapsed' to the sovereign