**Core Concept**
T cells and B cells are both types of lymphocytes that play crucial roles in the adaptive immune system. They share some similarities in their development, activation, and function, but also exhibit distinct differences.

**Why the Correct Answer is Right**
T cells and B cells both undergo clonal expansion and differentiation in response to antigen recognition. However, B cells are responsible for producing antibodies, whereas T cells are involved in cell-mediated immunity through direct killing of infected cells or modulation of immune responses. The main difference lies in their antigen recognition mechanisms: B cells recognize antigens through their surface-bound antibodies, whereas T cells recognize antigens presented by major histocompatibility complex (MHC) molecules on the surface of antigen-presenting cells.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because both T cells and B cells undergo clonal selection, a process where only those lymphocytes that recognize specific antigens are activated and expanded.
**Option B:** This option is incorrect because both T cells and B cells can undergo apoptosis, or programmed cell death, when they fail to recognize antigens or are otherwise eliminated from the immune response.
**Option C:** This option is incorrect because both T cells and B cells can be activated by cytokines, which are signaling molecules that promote or inhibit immune responses.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that B cells and T cells have distinct roles in the immune response, and their dysregulation can lead to various immune-related disorders, such as autoimmune diseases or immunodeficiencies.

**Correct Answer:** D.