Which is a handheld device that used to manually breathe for the patient on temporary basis?

The correct answer is a Bag Valve Mask.

A bag-valve mask (BVM), also known as a manual resuscitator, is a handheld device used to provide positive pressure ventilation to a patient who is not breathing or whose breathing is inadequate. It consists of a self-inflating bag, a one-way valve, and a mask that fits over the patient's face. The BVM is used to manually breathe for the patient on a temporary basis, until more definitive airway management can be established.