Which of the following code blocks returns a one-column DataFrame of all values in column supplier of DataFrame itemsDf that do not contain the letter X? In the DataFrame, every value should only be listed once.
Sample of DataFrame itemsDf:
1.+------+--------------------+--------------------+-------------------+
2.|itemId| itemName| attributes| supplier|
3.+------+--------------------+--------------------+-------------------+
4.| 1|Thick Coat for Wa...|[blue, winter, cozy]|Sports Company Inc.|
5.| 2|Elegant Outdoors ...|[red, summer, fre...| YetiX|
6.| 3| Outdoors Backpack|[green, summer, t...|Sports Company Inc.|
7.+------+--------------------+--------------------+-------------------+