The answer is
b. drawing a sample of the fluid that surrounds a fetus in the
uterus.
The fluid which is present in the amniotic sac is called as
amniotic fluid. The main imporatance of this fluid is to protect
the baby from shock, excange of the nutrients, water etc between
the mother and fetus. This fluid contains the fetal cells, as it
contians the fetel cells, for cytogenetic stuides this fluid will
be drawn from the amniotic sac, this process is called
amniocentesis.
