Explanation:

All statements are correct.

• The Siachen Glacier is located in the Eastern Karakoram range in the Himalayas, just northeast of Point NJ9842 where the LOC between India and Pakistan ends.

• NJ 9842 is the known boundary between India and Pakistan, but fewer know about 5Q 131 05 084, the number assigned to the Siachen Glacier by the Geological Survey of India (GSI), a disputed area between the two countries since 1984.

• The point NJ 9842 as it is the last mutually demarcated point between India and Pakistan as per the Karachi ceasefire agreement of 1949 and also the point where the Line of Control of the Simla Agreement ends. 

• The Siachen Glacier lies immediately south of the great drainage divide that separates the Eurasian Plate from the Indian subcontinent in the extensively glaciated portion of the Karakoram sometimes called the "Third Pole". Nubra river originates from Siachen Glacier.

Hence option 4th is correct.