**Core Concept**
Dapoxetine is a selective serotonin reuptake inhibitor (SSRI) that acts by increasing the levels of serotonin in the synaptic cleft, which in turn enhances the neurotransmission and delays ejaculation.

**Why the Correct Answer is Right**
Dapoxetine is specifically developed for the treatment of premature ejaculation (PE) due to its pharmacokinetic profile, which allows for rapid onset and short duration of action. This makes it an ideal treatment option for PE, as it can be taken on an as-needed basis without the need for daily dosing. Dapoxetine's mechanism of action involves the inhibition of serotonin reuptake, which increases the levels of serotonin in the synaptic cleft and delays ejaculation.

**Why Each Wrong Option is Incorrect**
**Option A:** Depression is typically treated with SSRIs like fluoxetine, sertraline, and paroxetine, which have a longer half-life and are not designed for on-demand use.
**Option B:** Psychosis is treated with antipsychotics, which are a different class of medications altogether.
**Option D:** Anxiety disorders are also treated with SSRIs, but not with dapoxetine specifically, as it has a unique pharmacokinetic profile.

**Clinical Pearl / High-Yield Fact**
It's essential to note that dapoxetine has a short half-life, which allows for rapid onset and offset of action, making it an ideal treatment option for PE. This also means that it may not be suitable for conditions requiring longer-term treatment.

**✓ Correct Answer: C. Premature ejaculation**