What is significant about ports $0$ through $1023?$

Question $2$Select one:

a$.$

They are the most efficient way to transfer data host$-$to$-$host due to compression

b$.$

They are the most efficient way to transfer data host$-$to$-$host due to cache

c$.$

They are regarded as highly secure in comparison to other ports

d$.$

They are often associated with particular application protocols