Which two services can you add safely, without conducting an additional site survey?

Your site has already been surveyed at 5 GHz for 802.11n VoWLAN services. Which two services
can you add safely, without conducting an additional site survey? (Choose two.)

A.
enhanced Layer 2 or Layer 3 security of the WLAN

B.
optional MFP client protection for Cisco Client Extensions Version 5 clients

C.
802.11n data services on the 2.4 GHz Frequency

D.
802.11n voice services on the 2.4 GHz Frequency

E.
new services (such as location) on both frequencies