The diagram given below refers to PCR. Identify the correct option.

Read the following statements and select the incorrect ones.

i) Downstream processing is one of the steps of polymerase chain reaction.

ii) Disarmed pathogen vectors are used to deliver desirable genes into host cells.

iii) Taq polymerase remains active during the high-temperature treatment during the denaturation of DNA.

iv) Pfu polymerase isolated from Pyrococcus furiosus is a thermostable bacterium used in the PCR technique.

v) In gel electrophoresis, the DNA fragments are separated based on their charge only.

Which of the following statements is incorrect about the PCR technique?