Why is statsborgerprøven only in Norwegian?

Statsborgerprøven (the Norwegian citizenship test) is only available in Norwegian, in Bokmål and Nynorsk. Samfunnskunnskapsprøven (the social studies test) is available in a wide range of languages. The difference seems arbitrary until you see what the two tests are actually for.

The two tests do different jobs

Samfunnskunnskapsprøven belongs to the permanent residence permit. The point is that you should know the society you live in: where to go when your child is ill, what rights you have at work, how elections work. That's knowledge that's just as useful whatever language you think in, which is why the test is translated.

Statsborgerprøven belongs to citizenship, and Norwegian is part of that requirement. The test being in Norwegian is part of that assessment.

What this means in practice

Your order of tests is worth thinking through.

If you can take samfunnskunnskapsprøven in Norwegian, it covers both tracks. You'll have completed the knowledge requirement for both residence and citizenship in one go.

If you take it in another language, you'll get permanent residence sorted, and statsborgerprøven will wait for later. That's not a setback. Most people take several years between the two applications anyway, and your Norwegian will improve in the meantime.

Bokmål or Nynorsk

You can choose, and both are available with audio. Choosing one isn't an advantage or a disadvantage, pick whichever you've read more of.