You are given a question and two statements numbered I and II. You have to ensure whether the data in the statements are sufficient to answer the question.
Question: What time did the bus leave today ?
Statements:
I. The bus normally leaves on time.
II. The scheduled departure is at 12 : 30.

Question: What time did the bus leave today ?

According to given information:
Statements:
I. The bus normally leaves on time.

This statement suggests that the bus usually leaves at its scheduled time, but it doesn't specify what time the bus left today. Therefore, Statement I alone is not sufficient.
II. The scheduled departure is at 12 : 30.​​

This statement tells us the scheduled time for the bus departure, but it doesn't confirm whether the bus actually left at this time today. The bus could have left earlier or later than the scheduled time. Therefore, Statement II alone is not sufficient.

Thus, the correct option (b) Neither I nor II is sufficient.