EGG Inc.'s preferred shares currently trade at $34.50. Each preferred share is convertible into 2 common shares at any time. The market price of the common shares is $14.50. In percentage terms, what is the effective conversion premium on the common share price if the pref shares are converted now?

a) 6.89%

b) 18.97%

c) 5.50%

d) 15.94%