In diagram of pBR 322, which identifies components correctly:

$\text{Correct answer: C}$ 

$\text{Option (A):}$ 

$?$ The 'rop' gene is responsible for deciding the copy number of the plasmid possible in the host organism.

$\text{Option (B):}$ 

$?$ The labels stated as Hind III and EcoRI show the restriction site in the specific location.

$?$ Those specific restriction enzymes can cut at that region of pBR322.

$\text{Option (C):}$ 

$?$ $am{p}^R$ and $te{t}^R$ ampicillin resistance and tetracycline resistant sites which are also called antibiotic resistant genes.

$\text{Option (D):}$ 

$?$ 'ori' sequence given here is the origin of replication. This is the region where the replication of the plasmid starts to increase its number of copies.

Hence, the correct answer is option (C)