It isn't possible for your Business admin to see what you have in your Dropbox while you're a member of the team. However, your admin does have control over the account and has the ability to remove access to the account and transfer its contents to another member.
Dropbox for Business admins have no control or access to your personal Dropbox. If you've linked your personal Dropbox to a company-owned computer or device, it will be subject to your organization’s policies.
This article refers to a feature unique to Dropbox for Business. Dropbox for Business is aimed at projects, groups, and other organizations that want to share the same Dropbox storage quota with all of its members. If you're interested in learning more or want to sign up, visit the Dropbox for Business webpage.