The system administrator has been notified that many users are having difficulty connecting to the
company’s wireless network. They take a new laptop and physically go to the access point and
connect with no problems. Which of the following would be the MOST likely cause?

A.
The certificate used to authenticate users has been compromised and revoked.

B.
Multiple war drivers in the parking lot have exhausted all available IPs from the pool to deny
access.

C.
An attacker has gained access to the access point and has changed the encryption keys.

D.
An unauthorized access point has been configured to operate on the same channel.

Explanation:
Wireless Access Points can be configured to use a channel. If you have multiple access points
within range of each other, you should configure the access points to use different channels.
Different channels use different frequencies. If you have two access points using the same
channel, their Wi-Fi signals will interfere with each other.
The question states that that many users are having difficulty connecting to the company’s
wireless network. This is probably due to the signal being weakened by interference from another
access point using the same channel. When the administrator takes a new laptop and physically
goes to the access point and connects with no problems, he is able to connect because he is near
the access point and therefore has a strong signal.