Which of the following is true of chicken pox -
The fluid of vesicle of chickenpox contains virus during the first 3 days of illness, but scab is no infective.

About other options
Option b

VZV does not grow in an experimental animal or chick embryo.
It can be grown in tissue culture cell lines → Human fibroblast, HeLa cells, Vero cells.

Option c

VZV is a DNA virus.

Option d

VZV can cross the placenta and infect the fetus.
The baby may develop two types of complications depending on the period of gestation:-
Virus not found in scab
Virus can be grown on the chick embryo
Caused by RNA virus
Does not cross the placental barrier