43.A 4-year-old boy presents with leukocoria (white pupillary reflex) in his right eye. Imaging reveals an
intraocular mass. Histology after enucleation shows small round blue cells forming FlexnerWintersteiner rosettes. Which genetic abnormality is most closely associated with this tumor?
(A) Translocation t(9;22) creating the BCR-ABL fusion gene
(B) Amplification of N-MYC oncogene on chromosome 2p
(C) Isochromosome 17q abnormality
(D) Germline mutation in RB1 tumor suppressor gene on chromosome 13q14