Ans given are diff Because options given in both Q are diff . In Q.18 you have to choose best out of given four which is IVC and in another Q more better ans than IVC is Umbilical vein because it has highest O2 conc followed by IVC. Simple rule: more the vessel is close to placenta more O2 conc will be there
It’s based on options … max is umbilical vein
It’s about the best option .
Best option