Explanation:

Only statement 1st is correct.

• The S-400 Triumf is a mobile, surface-to-air missile (SAM) system designed and developed in the 1990s by Russia’s Almaz Central Design Bureau for Marine Engineering as an upgrade to the S-300 family.
• China was the first foreign buyer to broker a government deal with Russia in 2014; while Saudi Arabia, Turkey, India and Belarus have all acquired, or expressed interest, in the system since.
• The S-400 Triumf air defence missile system will give a major boost to India’s capabilities to take out enemy fighter aircraft and cruise missiles at long range. The Indian Air Force (IAF) will induct the first unit of S-400 systems at a time when India is locked in a standoff with China in the Ladakh sector.
• China has already deployed two S-400 squadrons at Ngari Gar Gunsa and Nyingchi airbase in Tibet, across Ladakh and Arunachal Pradesh respectively.

Hence option 3rd is correct.