The correct answer is: 3.
The British divided the ceded part of Haryana into three sub-divisions: Gurgaon, Rohtak, and Hisar.
Option A is incorrect because the British divided the ceded part of Haryana into three sub-divisions, not one.
Option B is incorrect because the British divided the ceded part of Haryana into three sub-divisions, not three.
Option C is incorrect because the British divided the ceded part of Haryana into three sub-divisions, not seven.
Option D is incorrect because the British divided the ceded part of Haryana into three sub-divisions, not eleven.