**Core Concept**
Selective serotonin reuptake inhibitors (SSRIs) are a class of antidepressant medications that inhibit the reuptake of serotonin in the synaptic cleft, increasing its concentration and availability for binding to postsynaptic receptors. However, SSRIs can also interact with other medications through enzyme induction or inhibition, particularly affecting the cytochrome P450 system.

**Why the Correct Answer is Right**
SSRIs, particularly fluoxetine and paroxetine, are known to inhibit the cytochrome P450 2D6 (CYP2D6) enzyme, which is responsible for the metabolism of many other drugs. This enzyme inhibition can lead to increased blood levels of other medications, potentially causing toxicity or adverse effects. For example, fluoxetine can increase the levels of beta-blockers, such as propranolol, and other medications metabolized by CYP2D6.

**Why Each Wrong Option is Incorrect**
**Option A:** Fluoxetine is known to inhibit CYP2D6 and can affect the blood levels of other drugs, so this option is incorrect.
**Option B:** Paroxetine is also a potent inhibitor of CYP2D6 and can interact with other medications, making this option incorrect.
**Option C:** Sertraline, another SSRI, is a less potent inhibitor of CYP2D6 compared to fluoxetine and paroxetine, but it can still affect the blood levels of other drugs.

**Clinical Pearl / High-Yield Fact**
When prescribing SSRIs, it's essential to consider potential interactions with other medications and monitor patients closely for signs of toxicity or adverse effects.

**Correct Answer: D. Sertraline**