HURRY will mark brainliest

Decorous refers to:

diligent behavior

decadent behavior

dignified behavior

dangerous behavior

i say B.

Decorous

in keeping with good taste and propriety; polite and restrained.

Decorous refers to dignified behavior because something that is decorous is dignified, proper, and in good taste, like your decorous great-aunt who always wears a dress - even when she's only headed to the grocery store. The adjective decorous shares its origins with decoration.