Definition: 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".
Input: [header] How to maintain indoor fountains [title] Keep your fountain pump submerged in water at all times. [step] This will help circulate the water in your fountain and keep it filtered, in addition to minimizing the growth of algae. Your fountain pump may also become dry and burn out if it is not submerged in water consistently. <sep> (A) [substeps] Examine the water level around your fountain pump on a daily basis. This will allow you to become familiar with how often you need to add water to the fountain. (B) Some fountain pump models come with a valve that can be adjusted simply with the thumb button and the smallest screw. [substeps] It's the nucleus found on both front and rear of your fountain pump near the control panel. (C) [substeps] If your fountain pump is under water and you do not regularly run it under water, it is likely to develop algae. [title] Float your fountain when it is not running. (D) Make sure there aren't any cracks or other leaks in your fountain pump. [title] Keep your fountain pump in a central location that's protected from heat and humidity.
Output:
A