You need to recommend a solution to reduce the amount of unsolicited commercial instant messages.
What should you recommend?
A . From the Skype for Business admin center, modify the external communications settings for each user.
B . From the Skype for Business module, run the Set-CsTenantPublicProvider cmdlet.
C . From organization in the Skype for Business admin center, configure the external access settings.
D . From the Skype for Business module, run the Set-CsPrivacyConfiguration cmdlet.