Final answer:
The statement is False. Less than half of the pro-B cell population dies due to non-productive VDJh rearrangement.
Step-by-step explanation:
The statement "About half the pro-B cell population dies due to a non-productive VDJh rearrangement" is False.
During the maturation of pro-B cells, an enzyme called DNA recombinase randomly excises variable (V) and joining (J) segments from the light chain gene. These segments are spliced together, and most of the non-productive rearrangements are eliminated through regulatory mechanisms, such as programmed cell death or apoptosis. Therefore, only a small fraction of pro-B cells survive and progress to the next stage of B cell development. So, less than half of the pro-B cell population dies due to non-productive VDJh rearrangement.