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". 

Ex Input:
[header] How to change trackpad settings on macbook pro [title] Find the system preferences. [step] Starting from your main desktop screen there are two ways to find the system preferences where the mouse and touchpad settings will be located : [title] Bring your cursor to the bottom screen and find the system preferences application. [step] The icon looks like a box with three gears inside it. <sep> (A) Open that to find all your system preferences. [substeps] Alternatively, you can use the spotlight feature. (B) On macbook pro this icon resembles a round blue square with a horizontal green dot on it. On other applications this icon is actually a box with a gear, and is small in appearance. (C) It can be located on the taskbar or in the upper left-hand corner of the window. [title] Let the system preferences application perform its work. (D) [title] Click the customize key in the dialog box. [title] Follow the on-screen instructions to change the customization function.

Ex Output:
A


Ex Input:
[header] How to get into a good secondary school in england [title] Prepare by learning about the schools. [step] Around september to october of the year before you hope to join the new school, you'll want to go to open evenings or open days. These are evenings where the school is opened especially for prospective students to visit the school and take a look around. <sep> (A) Attending these events will give you access to knowledge about the school, find out how to study there, and see what the schools do on the weekends. [title] Break into the traditional role of the school counsellor. (B) You should also prepare by gaining experience in a specific school. These skills can help convince your parents and friends that you fit into a good secondary school. (C) [substeps] The website of english schools in scotland is a good place to start. There are websites specifically dedicated to english secondary schools in scotland. (D) [title] Attend as many of the open evenings as you can. [step] Make sure you organise the dates and get to the evenings with plenty of time to look around-you don't want to be rushed.

Ex Output:
D


Ex Input:
[header] How to clean a guinea pig's fleece bedding [title] Remove feces and food debris. [step] At the end of each day, remove any loose stools or food you see on the bedding. You can use a plastic scoop, a small vacuum, or a small broom and dust pan. <sep> (A) [substeps] If needed, use a rubber mallet to punch holes in the fabric a few inches over the soiled bedding. [title] Select a proper disinfectant. (B) Clean all bedding surfaces to give guinea pigs fresh, healthy food. [title] Move any parts of the bedding. (C) [title] Give the bedding a trial run to see how comfortable it is for your guinea pig. [step] Set a trial run daily for two weeks to see how the bedding feels. (D) Pick up anything off the bedding that you can easily see. [title] Place loose hay in a single corner.

Ex Output:

D