Question

What problems affected the South Vietnamese army after the Paris Peace Accords?

The troops were spread thin.
Desertions reached an all-time high.
They had very little air support.
Ammunition was scarce.
There was an outbreak of disease.
Most of them were poorly trained.

Answer 1

"Most of them were poorly trained" would be the best option from the list, since all the military training that had taken placed before was largely geared towards temporary assistance, not a long-term military strategy.