When there are 3 or fewer choices as buttons or in a dropdown, they will be rendered as buttons. When there are more than 3 choices as buttons or in a dropdown, they will be rendered as a dropdown. If there are more than 10 choices in a dropdown, the multiple dropdown messages will be sent with up to 10 choices in each messsage. For example, if your bot has a dropdown with 10 choices, the user will receive two messages: the first message will have a dropdown with 10 choices, and the second messge will have a dropdown with two choices.