Questions & Answers about Hún velur frekar salat en brauð.
They are (understood as) accusative objects of velur (“choose”), which takes the accusative case. These nouns are neuter and look the same in nominative and accusative singular, so you don’t see a form change. With nouns that show case clearly you would see it:
• Hún velur frekar kjúkling en fisk. (accusative: kjúkling, fisk)