Which of the following statements best describes atrial fibrillation?
A. The P wave precedes, follows, or is buried in the QRS complex
B. Disorganized and irregular atrial waves are accompanied by an irregular ventricular rate.
C. it causes an atrial rate of 240 to 350 beats/min in a sawtooth pattern of atrial depolarization.
D. It occurs earlier than normal, preceded by a P wave with a normal QRS configuration