Read the excerpt from act iv of hamlet.
ophelia:
larded with 'sweet flower;
which bewept to the grave did go
with true-love showers.
claudius: how do you, pretty lady?
ophelia: well, god 'ild you! they say the owl was a baker's daughter. lord! we know what we are, but know not what we may be. god be at your table!
how does the excerpt reveal ophelia’s character development?
she has become more romantic.
she expresses an increased religious devotion.
she has lost her ability to think logically.
she is plotting revenge for her father’s death.

Okay... judging by the fact that you need help with this question... you probably read the spark-notes version of Hamlet LOL! But that's okay I feel you because I did the same thing.
 
But basically at this point in the story, Ophelia has lost her mind. She's talking all kinds of nonsense. The reason why is a combination of the fact that Prince Hamlet rejected her. ND Hamlet kinda sorta killed her father. But she doesn't know that. She just know's that he's been killed. And it pushed her over the edge.

So the answer to your question is the third option. Ophelia has gone coo-coo for CoCo Puffs.

Hope this helped.