To determine which letter is never used when printing the calendar featuring full names of all the days of the week and months, we must examine these names:
- Days of the Week: Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday
- Months of the Year: January, February, March, April, May, June, July, August, September, October, November, December
After examining these words, let's identify the presence of each letter from the provided options:
- W: Used in "Wednesday"
- G: Used in "August"
- K: Not used in any day or month
- V: Used in "November"
Thus, the letter that is never used in printing a calendar with the full names of days and months is K.