Answer:
The correct answer is- cortex
Step-by-step explanation:
Thymus is the primary lymphoid organ where the development and maturation of T cell takes place. Thymus is bilobed and each lobe is divided into lobule which has two compartments a cortex(outer) and a medulla(inner).
The immature T progenitor cells reach to cortex region of thymus where their growth and differentiation occur. In the cortex, these T progenitor cells become mature and then migrates to the medullary region where they go thymic selection after encountering macrophages and dendritic cells. So the correct answer is cortex.