Which of the following is the main cause of network failure? A. cables that break
B. peripherals that get in the way
C. storms
D. human error

Possibly A or C

Explanation:

answer; i believe the answer is tls,transport layer security;

to change your username, you must:

1) make sure what the username you want to change to is allowed in this community

2) contact a administrator (for example, jaysl)

3) through pm, tell the admin what you want to change to

4) if the username is allowed, it will be changed in a matter of seconds (minutes at most)

~