Since this is an open question with no choices, I am answering with what I think will best fill in the blank. Note: I do not know exactly what answer they are looking for.
The best answer is: REM
REM is the stage of sleep where dreaming occurs. REM stands for Rapid Eye Movement. Exactly as the title says, REM sleep is characterized by fast back and forth movement of the eyes.
Explanation:
I think the first one is the answer
Principal,
We will dearly miss you. You have not only made this school great, but you have also made us, the students, great. We thank you for all your hard work and dedication that you put into this school. We wish you farewell and hope you enjoy your retirement.
