Final answer:
The gene that can be mapped to the intracellular messaging abnormality linked to cell maturation and activated by CD19+ cells is CD34.
Step-by-step explanation:
The gene that can be mapped to the intracellular messaging abnormality linked to cell maturation and activated by CD19+ cells is CD34 (option D).
CD34 is a cell surface antigen that is found on hematopoietic stem cells, which are cells responsible for giving rise to all the different types of blood cells, including mature CD19+ cells. The activation of this gene plays a crucial role in the maturation of these cells.
Therefore, the correct answer to this question is option D) CD34.