The Citta does everything.
Fragment of a letter to a disciple, year not given but most likely after 1979.
'. . . The term Upadana Khandhas should not be called the "Grasping Khandhas". The Khandhas are so to speak "foreign matter" and they go their own way according to the laws of nature. The grasping is in the Kilesas which are infused in the Citta, using the power of the Citta and they grasp and hold tight to the Khandhas. Therefore they should truly be called the "Grasped Khandhas". The only sense in which "Grasping Khandhas" can be used correctly is that the Khandhas are the (passive) agents of the grasping Citta and so go about grasping this and that in the outer world. Like a man who makes a Robot and uses it to promote his grasping desires. To call it a grasping Robot is only a way of speaking and not really correct. The reason why most people talk about the "Grasping Khandhas" is that they have read books written or translated by people who don't understand Dhamma. To go talking without a proper understanding of the underlying principles is likely to be "Parrot talk".
I hope this helps.
Pa~n~navadho . . .'