**Core Concept**
The question tests the understanding of how local anesthetics exist in their ionized and non-ionized forms at physiological pH, which is around 7.4. **pKa** values of local anesthetics determine the proportion of ionized to non-ionized forms.

**Why the Correct Answer is Right**
Since the correct answer isn't specified, we'll discuss the general principle: Local anesthetics with a **pKa** closer to physiological pH will have a higher proportion of both ionized and non-ionized forms. However, for a local anesthetic to have its maximum ionized form at physiological pH, its **pKa** should be higher than 7.4, as the ionized form increases with decreasing pH (or increasing acidity) relative to the **pKa**.

**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific local anesthetic, we cannot directly address why it's incorrect, but generally, options can be eliminated based on their **pKa** values.
**Option B:** Similarly, without specifics, we look for **pKa** values significantly different from physiological pH.
**Option C:** This would be incorrect if its **pKa** is far from the physiological pH range.
**Option D:** Without knowing the correct answer, we assume this might be the correct choice if its **pKa** is appropriately higher than 7.4, but this depends on the actual options provided.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the **ionized form** of local anesthetics is the active form that blocks **sodium channels**, but the **non-ionized form** is necessary for penetration through the **lipid cell membrane**.

**Correct Answer:** Correct Answer: D. Lidocaine