The Choice tool is a simple poll, i.e. a single question with a certain number of suggested answers. The teacher can use a Choice activity to get quick feedback about something to do with the course you are taking.
Most commonly choices deal with matters of knowledge, i.e. a teacher can use a choice to determine what skill level his group has in a certain subject and adapt his teaching accordingly.
Another use of the choice is when a teacher allows students to choose a date and time for a learning session or an exam.
It is also possible for a teacher to use a Choice to allow students to choose which group they want to belong to, even limiting the maximum number of members.
It is possible that a teacher will ask you to answer the same Choice more than once, so that he/she can see if your knowledge/perception of a subject has changed during the course.
An example Choice:
Once you have answered a choice, you will in most cases see the results listed. The results may show students divided over the different options (as in the example above) or just the number of students that chose each option. (This view is used when the question is more personal to protect your privacy.)