the answer is the seconf one
In some aspects, yes but these have recently been outweighed with the ad boycott youtube has not to mention google plus wasn't the most popular, to begin with, but in an overall sense yes as the name google is more often used than Facebook or twitter
A burn-in test is a test which is usually performed on a system or component by running it for a long time in order to bring out any errors or system failures etc.
While doing it on CPU the data must be backed up as any kind of error or failure may result in the loss of data, at time systems can be repaired to retrieve data but still there is no guarantee, backing up is the best option.
Answer: A. A method of access control that allows a user to log on to a system and gain access to other resources within the network via the initial logon
Explanation: key distribution center ( KDC) is a system that is used to provide access to a particular network user who shares data which are either private or regarded as sensitive.
It is a form of encryption that allows multiple system within the same network through the use of uniquely secured tickets used to setup a secure connection which gives room for data to be shared.
KDC makes use of cryptographic techniques to prove the validity of a user and grants a ticket permission access. The user present the ticket of permission to the system which then validates it and grant access to the user.
Example of security system that adopts KDC include kerberos.