What is Castells $(1996)$ idea of the $$space of flows$?$

a$.$

Virtual terrains created by webs of electronic communication which do not exist in any particular place

b$.$

Physical spaces where manufacturers could easily access users$$ personal information

c$.$

Quasi$-$virtual realms where artificial intelligence would control and alter materials in the real world

d$.$

Spaces where human beings and technology would be virtually indistinguishable from each other