Which sentence contains an intransitive action verb? Disagreements mounted between the North and the South.
The North demanded tariffs to protects its products.
The Northers and Southerns fought a war with each other.
Most considered slavery the chief cause of the war.

1. in which sentence is the underlined portion a predicate nominative? for astronauts, going into space to repair orbiting equipment becomes a challenge. for astronauts, going into space to repair orbiting equipment becomes tricky. for astronauts, going into space to repair orbiting equipment becomes challenging. for astronauts, going into space to repair orbiting equipment becomes frequent.