In Research by Siegel Et Al

In research by Siegel et al. (2008) on persuading people to become organ donors, which of the following appeals led to the most organ donation registrations?

A) An appeal that described the emotional impact on people's lives.
B) An appeal that emphasized the inconsistency of believing organ donation is good but failing to sign up.
C) An appeal that refuted organ-donation myths.
D) An appeal that emphasized acting on one's desire.