Final answer:
In the television show Grey's Anatomy, Derek gets married to Meredith only once.
Step-by-step explanation:
The question asking about the number of times Derek got married to Meredith is based on the television show Grey's Anatomy.
In the show, Derek Shepherd, one of the main characters, is married to Meredith Grey. However, Derek only gets married to Meredith once in the series.
Therefore, the correct answer is A) Once.