Miscarriage: TMI and trigger warning! What is what?

My doctor told me this was “the pregnancy” when I asked what I had just passed. Can anyone tell what is what? I’m thinking the placenta looking sac was the gestational sac maybe? But the other piece was twisty like an umbilical cord, I was only 6 weeks when I miscarried so not sure if babies even have that stuff at that point. Any ideas?

Also for reference, positive pregnancy test, HCG was at 400