For Norway’s $890 billion sovereign-wealth fund, the investment risks stemming from monetary policy have never been greater. Like most global investors, the Oslo-based fund is trying to navigate uncharted terrain as central banks across the world push out stimulus to protect economic growth and spur inflation. “Monetary policy does affect pricing in today’s market to such an extent that monetary policy itself has been a risk you have to watch,” Yngve Slyngstad, chief executive officer of the fund, said in an interview on Wednesday at Bloomberg’s New York headquarters.