Explanation
\textbf {Step1: Draw a relevant figure.}
At 9 O'clock the minute hand will be at 12 and the hour hand will be at 9 as shown in figure.
\textbf {Step 2: Identify the angles.}
From the above figure, we can say that the angle between hour hand and minute hand of the clock is 90,270.
\textbf {Hence, option B is correct.}
Please disable the adBlock and continue. Thank you.