The correct answer is A. 1.43%.
The Scheduled Tribe (ST) population of Jammu and Kashmir is 1,176,489, which is 1.43% of the total ST population of India, which is 86,116,662.
Option B is incorrect because the ST population of Jammu and Kashmir is not 5% of the total ST population of India.
Option C is incorrect because the ST population of Jammu and Kashmir is not 10% of the total ST population of India.
Option D is incorrect because the ST population of Jammu and Kashmir is not 15% of the total ST population of India.