**Core Concept**
The question refers to the activation of B cells and the subsequent production of a specific class of immunoglobulins (antibodies) following the injection of lymphokines. This process is an example of a secondary immune response, where the immune system is able to mount a more rapid and effective response to a previously encountered antigen.

**Why the Correct Answer is Right**
The correct answer is related to the concept of isotype switching, where activated B cells undergo a change in the class of immunoglobulins they produce. In this case, the injection of lymphokines triggers the production of the same class of immunoglobulins, indicating that the B cells have switched to produce this particular isotype. This process is mediated by the activation of specific transcription factors, such as interferon-gamma (IFN-γ) and IL-4, which induce the expression of genes involved in isotype switching.

**Why Each Wrong Option is Incorrect**

* **Option A:** This option is not relevant to the concept being tested.
* **Option B:** This option is incorrect because it does not accurately describe the process being tested.
* **Option C:** This option is incorrect because it is not related to the concept of isotype switching.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that isotype switching is a critical aspect of the adaptive immune response, allowing the immune system to tailor its response to the specific type of pathogen encountered. This process is mediated by the interaction between T cells and B cells, and is a key factor in the development of immune memory.

**Correct Answer:** D.