Which one of the following events immediately follows the entry of a spermatozoan into an oocyte

$A$ : The first sign of growing foetus may be noticed by listening to the heart sound through the stethoscope.
$R$ : By the end of second month of pregnancy, the foetus develops limbs and digits.

Which one of the following is incorrect match?

Ontogenetically liver and pancreas are or During embryonic development pancreas and liver develop from which germinal layer

The function of egg cell is/are