This section is at least partly lower limb because you can see the hip bone and tibia on one side

The primitive heart can be seen within the pericardial sac, therefore it is the thorax

The oesophagus can be seen, therefore it must be the abdomen 

At least partly cervical, because there is oesophagus present, postero-lateral to the trachea

This is the thorax because you can see lung tissue either side of the midline

No structures or organs of the thorax can be seen here, so it has to be the cervical region

This is the cervico-thoracic junction because you can see parts of the thoracic inlet