What does size scalability mean in distributed systems? $(2$ points$)$

$($a$)$ Size scalability means that the machine can become bigger without any noticeable loss of performance.

$($b$)$ Size scalability means that more users and resources can be added to the system without any noticeable loss of performance.

$($c$)$ Size scalability means that the users and the resources may lie far apart, but the fact that communication delays may be significant is hardly noticeable.

$($d$)$ Size scalability means that a system can be easily managed even if it spans over many independent administrative organizations.