Which of the following is required as inducer$(s)$ for the expression of $Lac$ operon?

In which of the following are monocistronic genes found?

Given below is the representation of the $lac$ operon of $E. coli$. Identify $I$ and $II$ from the options given below.

$I$

Promoter

$II$

$Z$

$Y$

$A$

Select the two correct statements out of the four $(i-iv)$ statements given below about the lac operon.
$(i)$ Glucose or galactose may bind with the repressor and inactivate it.
$(ii)$ In the absence of lactose,the repressor binds with the operator region.
$(iii)$ The $z$-gene codes for permease.
$(iv)$ This was elucidated by Francois Jacob and Jacques Monod.
The correct statements are:

How many operons are present in the $nif$ gene cluster of $Klebsiella$ $pneumoniae$?

Where are the regulatory genes located in an operon?