Which feature distinguishes a morula from a blastula?

$A$ post-gastrula embryo contains:

Identify the correct labeling and its function from the given diagram of a developing fetus.

The first sign of the growing foetus may be noticed by listening to the heart sound carefully through the stethoscope. The embryo's heart is formed . . . . . . .

After which stage does cleavage stop?

Assertion: In the morula stage,cells divide without an increase in size.
Reason: Zona pellucida remains undivided until cleavage is complete.