The core idea
Long-term yields can rise because expected future short rates increase, inflation uncertainty grows, the term premium rises, government bond supply expands or investors demand greater compensation for holding duration.
What is happening underneath
Separating expected policy rates from term premium is essential because two identical yield moves can carry very different macro messages.
How investors should read it
Long yields are therefore both an economic expectation and a market-clearing price for duration risk.
The same market move can carry different information depending on which maturity, issuer and risk premium is changing. Read the question together with the underlying concepts rather than treating one price move as a universal signal.