In the human body, the 'Thymus gland' is most active during childhood and plays a crucial role in the maturation of: MCQ with Answer and Explanation

The thymus is a lobulated lymphoid organ located in the upper part of the thoracic cavity, near the heart. It is most prominent and active during childhood and begins to atrophy (involute) after puberty. Its primary function is to provide a microenvironment for the differentiation, selection, and maturation of T-lymphocytes (T cells), which are crucial for cell-mediated immunity. The thymus also secretes hormones like thymosin, which aid in T-cell development.