Which of the following is a risk factor for thedevelopment of thromboembolism in patients with thetachycardia-bradycardia variant of sick sinus syndrome?(B)A. Age greater than 50 yearsB. Atrial enlargement C. Diabetes mellitusD. Prothrombin 20210 mutationE. None of the above; there is no increased risk ofthromboembolism with the tachycardia-bradycardiavariant of sick sinus syndrome.