A company uses Skype for Business Online.
You need to ensure that all employees can search for and add Skype consumer contacts.
What should you do? contacts the users must connect through the Skype consumer client , and must log in with Office 365 credentials.

A.
Instruct all employees to use the Skype for Business client, and connect to Skype for Business Online by
using their Skype ID credentials.

B.
Instruct all employees to use the Skype consumer client, and connect to Skype for Business Online by using
their Skype ID credentials.

C.
Instruct all employees to use the Skype consumer client, and connect to Skype for Business Online by using
their Office 365 credentials.

D.
Instruct all employees to use the Skype for Business client and connect to Skype for Business Online by
using their Office 365 credentials.

Explanation:

The client for Skype for Business Online.is Skype for Business client. To be able to search for Skype consumer
References: https://technet.microsoft.com/en-us/library/dn705313.aspx