The standard that is supported by some Aruba APs and can enable a customer to accurately locate wireless client devices within a few meters is A) 802.11mc.
802.11mc is an IEEE standard that enables computing devices to measure the distance to nearby Wi-Fi access points using a technique called Fine Timing Measurement (FTM). FTM uses precise timestamps to calculate the round-trip time of Wi-Fi frames between the device and the access point, and then converts it to a distance estimate. By using multiple access points and triangulation methods, the device can determine its location with high accuracy1.
According to the Aruba document 802.11mc Support, this feature is supported on 500 Series, 510 Series, 530 Series, 550 Series, 560 Series and 570 Series access points. These APs act as FTM responders to time measurement queries sent from a client. To configure the AP to send FTM responses, you need to enable the ftm-responder-enable parameter in the WLAN SSID profile1.

Option C is the only action that configures the DHCP relay on the SVI of VLAN 1000 on the CX 8360 switches. DHCP relay is a feature that allows a switch to forward DHCP requests from clients in one subnet to a DHCP server in another subnet. DHCP relay is required when the DHCP server and the clients are not in the same broadcast domain1.
Option C uses the following commands:
interface vlan 1000: This command enters the interface configuration mode for the SVI of VLAN 1000, which has an IP address of 10.102.39.1/24 and is used for wireless clients.
ip helper-address vrf default 10.200.1.100: This command configures the IP address of the DHCP server as a helper address for the SVI, which means that the switch will forward DHCP requests from clients on VLAN 1000 to this address. The vrf default parameter indicates that the SVI and the DHCP server are in the same VRF.

BSS coloring is a mechanism that helps identify the BSS Basic Service Set. A BSS is a set of interconnected stations that can communicate with each other. BSS can be an independent BSS or infrastructure BSS. An independent BSS is an ad hoc network that does not include APs, whereas the infrastructure BSS consists of an AP and all its associated clients. on the same channel and differentiate them from other BSS on the same channel12. Each BSS is assigned a color code, which is a 6-bit value that is carried in the PHY header of the Wi-Fi frames12. By using BSS coloring, the APs and clients can reduce the threshold for interference detection and avoid unnecessary backoff or retransmissions when they detect frames from other BSS with different colors12. This can improve the spectral efficiency and throughput of the network12. The other options are incorrect because they do not describe the primary benefit of BSS coloring.