Answer:
Option C. Study group-2:15.
Step-by-step explanation:
A daily organizer is a tool used by people with fixed responsabilities either as a task reminder, or a performance enhancer in one's daily routine.
It is only logical to include daily tasks in this organization tool, and a study group scheduled for a specific time each day is an appropiate addition. As for the rest of the option, they are one-time events, and therefore, cannot be added in a daily organizer.