Alpha complementation is an indicator of lacZ system. Which of the statement is incorrect for it? __________

A.One portion of the lacZ gene known as minigene is present in the plasmid
B.Another portion is present in the host itself
C.If they both are allowed to combine in the presence of IPTG, X-gal and ampicillin, blue colonies are observed
D.If insert is also present along with host and plasmid, it results in the formation of blue colonies