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 exercise to prevent blood clots [title] Get up and move around. [step] Whether you're traveling by train, plane, or automobile, long-distance travel involves a lot of sitting. When you sit, you decrease circulation in your legs-especially if you sit with your legs crossed or with one foot under you. <sep> (A) If you are on a train or coach, the seat underneath you always feels flat, as if you are sitting. While there are good ways to stretch out your legs, there is not a lot a group of people can do. (B) This will help promote blood circulation to your feet. It will also keep you from rubbing your legs in an annoying manner-you can't promote blood flow when you're sitting on one leg. (C) [substeps] You can exercise while you drive or driving, although getting up and down on the exercise train can significantly improve circulation. You can also listen to music while you exercise, which will also help to prevent blood clots. (D) [substeps] If you're on a plane, try to get an aisle seat so you can get up and move around more easily. Ideally, you want to get up and stretch your legs or walk up and down the aisle once every hour or so.

Ex Output:
D


Ex Input:
[header] How to include spanking in child discipline [title] Find a private area. [step] Conducting this type of discipline in a private area preserves the dignity of your child and prevents unnecessary embarrassment. The focus should be on discipline and additional embarrassment for your child should be minimized. <sep> (A) [substeps] Look for a private area free of distractions. Have a book or other non-distracting object nearby to quiet the child and yourself. (B) [substeps] Most experts are adamant that children should never be spanked under any circumstances. Nonetheless, some parents believe that spanking is the best way to get children to adhere to rules. (C) [substeps] If you have permission to do so, choose a private area to discipline your child in private. It will help your child feel at home instead of surrounded by other adults. (D) There are a wide variety of private areas you can think about according to age and the individual or group of children that you're spanking. [substeps] Children should have close supervision at all times.

Ex Output:
B


Ex Input:
[header] How to act perky [title] Seek out positive people. [step] If you want to be perky, a positive attitude is key. Seek to surround yourself with positive, happy people. <sep> (A) Consider making a list of positive people in your life. Chances are, you should include all of the people who you feel and know you love. (B) On the contrary, individuals who surround themselves with negative, unencouraging people tend to decrease their likelihood of resembling perky. Positive people go to every positive event and do what they can to make life better. (C) You'll end up feeling happier and, as a result, acting perkier. [substeps] Make plans with people who have positive attitudes. (D) Having positive people around means having a social network. People who are positive are optimistic, affectionate, and generous.

Ex Output:

C