Which author has the most credible and reliable source of information? an author who includes in-text citations and a works cited page an author with an impressive-sounding job an author who is being paid by an advertising company to write an author with a well-designed website

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.