In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".

[header] How to stop getting distracted by your phone when studying [title] Switch on the " do not disturb " mode. [step] Iphone and android phones have settings that allow you to mute all notification beeps and calls during a time of your choosing. When you want to study, you should use your quick settings to turn this mode on, and don't return to it until you have completed your study session. <sep> (A) [substeps] You will need to be enabled for automatic notifications when you update, or when you call or text. [title] Cut off " show & hide " notifications. (B) [substeps] On iphones, swipe up from the home screen to access your basic settings. Tap the moon shape and this function will be enabled. (C) [substeps] Attempting to turn off this mode will keep you from focusing on studying, especially when you may be home studying, since distractions can interrupt your study. [title] Look at the screen of your phone. (D) Ensure your device is secure and in working order before proceeding. [title] Answer the teacher's questions calmly.
B