**Core Concept**
Pharmacovigilance is the process of monitoring and managing the safety of medications after they are approved for use in humans. It involves detecting, assessing, and preventing adverse effects of medications to ensure their safe use.

**Why the Correct Answer is Right**
The primary goal of pharmacovigilance is to identify and mitigate potential risks associated with medications. This is achieved by collecting, analyzing, and interpreting data on adverse drug reactions (ADRs) and other safety concerns. Pharmacovigilance programs typically involve collaboration between healthcare professionals, regulatory agencies, and pharmaceutical companies to ensure the safe use of medications. This process is essential for post-marketing surveillance, which helps to identify previously unknown side effects and adjust medication labels and guidelines accordingly.

**Why Each Wrong Option is Incorrect**
**Option A:** Pharmacoeconomics is the study of the economic and financial implications of medications, which is a related but distinct field from pharmacovigilance.
**Option B:** Pharmaceutical development is the process of creating new medications, which is a precursor to pharmacovigilance but not the same thing.
**Option C:** Clinical trials are studies that evaluate the safety and efficacy of medications during the development process, but pharmacovigilance occurs after a medication has been approved for use.

**Clinical Pearl / High-Yield Fact**
Pharmacovigilance is a critical component of ensuring medication safety, and its importance cannot be overstated. A well-functioning pharmacovigilance system can prevent medication errors, reduce adverse drug reactions, and ultimately improve patient outcomes.

**Correct Answer: D. Adverse drug reactions.**