ED got game to play!?

Today we have the ED2 lecture, it was not Dr aissa but Mr leong as our ED lecturer this sem , we can feel the diffrences, during lecture of ED2 our lecture said wanna give us playing one game(sound like interesting), but...that is to determine which one is HP(high pass) and which one is LP (low pass)-.-"'(It is easy but I dunno the answer because my Y1sem. 1 CT is..) After Ed2, we have a break and continuous our lecture with mr leong (agains ~ z.z) but diffrences subjects ( Today whole day lecture class is with Mr leong). this was the second lecture teach us two subjects in one sem. since Mr Ooi cy.



"Answer is B"