[单选题]
When a positronium atom (electron + postw;t72) w,i*ctheje u itron) decays, it emivwug0 rd;z2;3v4fjd 9 f kmdp5ts two photons. What add4r ;5v9mvp3dwufjzkf0g; 2re the energies of the photons?
A. 0.511 MeV and 1.022 MeV
B. 0.225 MeV and 0.285 MeV
C. 0.256 MeV and 0.256 MeV
D. 0.511 MeV and 0.511 MeV
