Exam 70-333 topic 1 question 32 discussion

Your company purchases a subscription to Microsoft Office 365.
The company has a strict firewall and an Internet usage policy. Only required ports are open between the internal network and the Internet.
Users report that they can use the following Office 365 features:
✑ Access email by using Outlook Web App.
✑ Establish chat sessions by using instant messaging (IM).
The users also report that they fail to join online audio conferences and online video conferences.
You need to open outbound ports on the firewall to ensure that the users can join online audio and video conferences.
Which two ports or port ranges should you open? Each correct answer presents part of the solution.