You are the messaging engineer for your company. Your company has a main office and four branch offices. Each office is configured as a separate IP subnet.

Your network consists of a single Active Directory site named Default-First-Site.

You need to design an Exchange organization that meets the following requirements:

Each office must contain a Mailbox server.

Each office must contain only one Exchange server.

Route all mail messages sent between users of your company through the main office only.

Route all mail messages sent between users of your company with Transport Layer Security (TLS).

Which three elements should your design include? (Each correct answer presents part of the solution.

Choose three.)