To answer this question, you need to have knowledge about the players who have achieved the milestone of being the only Centurion in T20 Internationals.
Let's go through each option to understand why it is correct or incorrect:
Option A) Brendon McCullum - This option is incorrect because Brendon McCullum is not the only Centurion in T20 Internationals. Several other players have also achieved this milestone.
Option B) Chris Gayle - This option is correct because Chris Gayle is indeed the only player to have scored a century in T20 Internationals. He achieved this feat on September 11, 2007, against South Africa.
Option C) Shaun Marsh - This option is incorrect because Shaun Marsh has not scored a century in T20 Internationals.
Option D) Tillekeratne Dilshan - This option is incorrect because Tillekeratne Dilshan has not scored a century in T20 Internationals.
The correct answer is B) Chris Gayle. This option is correct because Chris Gayle is the only player to have scored a century in T20 Internationals.