The correct answer is: 2016.
Shri Shakti Express is a weekly superfast train service connecting Secunderabad in Telangana with Hazrat Nizamuddin in Delhi. It was flagged off by Prime Minister Narendra Modi on 28 February 2016. The train runs with 22 coaches, including 1 AC 2-tier, 3 AC 3-tier, 12 Sleeper Class, 3 General Unreserved and 2 Luggage cum Brake Van coaches. It has a scheduled speed of 55 kmph and covers the distance of 1,460 km in 28 hours and 55 minutes.
Option A: 2013 is incorrect because Shri Shakti Express was not flagged off in 2013.
Option B: 2016 is the correct answer because Shri Shakti Express was flagged off in 2016.
Option C: 2015 is incorrect because Shri Shakti Express was not flagged off in 2015.
Option D: 2014 is incorrect because Shri Shakti Express was not flagged off in 2014.