You are incorrect - the best interpretation of the rhythm strip in our patient is atrial fibrillation.

Your choice: Multifocal atrial tachycardia
This rhythm strip shows multifocal atrial tachycardia. The characteristic features demonstrated here include discreet P waves of three or more different morphologies, a P wave preceding each QRS and a rate greater than 100 per minute. This type of rhythm is typically seen in patients with severe respiratory disease.