**Core Concept**
The Millennium Development Goals (MDGs) are a set of eight international development goals for the year 2015 that were established following the Millennium Summit of the United Nations in 2000. These goals aimed to address extreme poverty, hunger, disease, gender inequality, and access to education and healthcare.

**Why the Correct Answer is Right**
The MDGs were a critical component of the United Nations' Millennium Declaration, signed by 189 countries. The goals included reducing poverty and hunger, improving maternal and child health, combating diseases, ensuring environmental sustainability, and promoting global partnership for development. The target date of 2015 was set to achieve these ambitious goals. The MDGs were a significant step towards achieving the United Nations' Sustainable Development Goals (SDGs), which were launched in 2015.

**Why Each Wrong Option is Incorrect**
**Option A:** 2005 is too early to achieve the MDGs, as the goals were only set in 2000 and required a significant amount of time and effort to implement.
**Option B:** 2010 is also too early, as the MDGs were designed to be achieved over a 15-year period, from 2000 to 2015.
**Option D:** 2020 is too late, as the MDGs were a specific set of goals for the year 2015, and extending the deadline would have undermined their significance and impact.

**Clinical Pearl / High-Yield Fact**
The MDGs were a critical step towards achieving the Sustainable Development Goals (SDGs), which were launched in 2015 and aim to address the same issues, but with a broader and more ambitious scope.

**Correct Answer:**
✓ Correct Answer: C. 2015