How are modified genes introduced into the host cells for preparing third-generation vaccines?

Introduced by cooling and then icing the cells

Introduced by first giving a heat shock and then cooling the cells

Introduced by making new pathways for pathogens

How are modified genes introduced into the host cells for preparing t

1.	How are modified genes introduced into the host cells for preparing third-generation vaccines?
A.	Introduced by DNA injection
B.	Introduced by cooling and then icing the cells
C.	Introduced by first giving a heat shock and then cooling the cells
D.	Introduced by making new pathways for pathogens
Answer» B. Introduced by cooling and then icing the cells