To answer your question, let's go through each option to understand why it is correct or incorrect:
Option A) Octillion - This option is incorrect because octillion comes after septillion, not trillion.
Option B) Decillion - This option is incorrect because decillion comes after nonillion, not trillion.
Option C) Quadrillion - This option is correct. Quadrillion is the number that comes after trillion.
Option D) Undecillion - This option is incorrect because undecillion comes after decillion, not trillion.
The correct answer is C) Quadrillion. This option is correct because quadrillion is the number that comes after trillion.