Respuesta :

hxileym
sabes

because conocer is used more when you personally know someone/thing
saber is used when you know facts about someone or something.

se is conjugated in the yo form 
sabes is conjugated in the tu form so this one is correct because you are asking someone if they know where the party is.
The answer is sabes, because it means "Do you know", so the others don't make sense.