The correct answer is D.
OBJ-5.4: The most likely reason is signal attenuation from the new flag being placed between the signal path which may be obstructing the line-of-sight between the antennas. Based on where the flag is precisely located, it is possible to only block the signal when the wind is blowing in a certain direction. This would lead to the intermittent connectivity experienced by the users caused by the signal attenuation when the flag is blocking the communication path between the antennas. DHCP exhaustion occurs when the DHCP server runs out of available IP addresses and stops issuing DHCP bindings. If DHCP exhaustion occurred, the users would not have received an IP address and they would have no connectivity instead of intermittent connectivity. The question does not mention anything about the antennas being moved or replaced recently, so it is unlikely to be an issue with the antennas since they worked previously with the same wireless network and distanced. Bandwidth saturation occurs if too many devices are on one WAN link, but nothing in the question indicates that more users have been added and causing an issue.