What is the primary difference between scalability and elasticity in system architecture$/$cloud computing?

a$.$ Scalability refers to the system's ability to increase in capacity based on demand, whereas elasticity refers to the ability to increase and decrease in size as needed.

b$.$ Scalability is about the system's ability to reduce its size, whereas elasticity is about increasing size only.

c$.$ Scalability is a measure of the system's performance improvement when additional resources are added, while elasticity measures the speed at which a system adapts to load changes.

d$.$ Scalability focuses on system growth in a single dimension, such as storage, whereas elasticity involves multi$-$dimensional growth and shrinkage, such as compute, storage, and bandwidth.