Question

hamlet, part 8: themes
hamlet: hear you, sir,
what is the reason that you use me thus?
i lovd you ever: but it is no matter;
let hercules himself do what he may,
the cat will mew and dog will have his day. exit. (180)
claudius: i pray you, good horatio, wait upon him. exit horatio.
to laertes: strengthen your patience in our last nights speech;
well put the matter to the present push.
good gertrude, set some watch over your son.
this grave shall have a living monument: (185)
an hour of quiet shortly shall we see;
till then, in patience our proceeding be. exeunt.
why does queen gertrude think that hamlet is causing a fuss in the graveyard?
she thinks that he truly loved ophelia and is overwhelmed with grief.
she thinks that the funeral is bringing back memories of his father’s death.
she thinks that he wants to get revenge on laertes.
she thinks that his behavior is a sign of his madness.

Explanation:

In the context of "Hamlet", Queen Gertrude has observed Hamlet's erratic and disturbed behavior throughout the play. His actions in the graveyard, along with his prior strange conduct, lead her to believe his behavior is due to his madness, rather than the other options (loving Ophelia's grief, father's death memories, or revenge on Laertes) which don't align as closely with her perception of his mental state.

Answer:

She thinks that his behavior is a sign of his madness.