27. What are the differences between a passive tag and an active tag?

(a) Active tags can use cheaper readers; passive tags’ readers are more expensive

(b) Passive tags’ frequencies can be tuned easier; active tags do not have a frequency range

(c) Active tags are mostly used for item‑level tacking of inventory items

(d) Passive tags do not have the ability to have sensors and active tag can have sensors

(e) Passive tags are EPC compliant and active tags are not EPC compliant

(f) None of the above