Which vitamin works closely with folic acid and is primarily found in animal products?

Vitamin B12 is the correct answer because it plays a crucial role in various metabolic processes and works closely with folic acid, particularly in DNA synthesis and the formation of red blood cells. This vitamin is essential for maintaining healthy nerve function as well.

Vitamin B12 is primarily found in animal products such as meat, fish, dairy, and eggs, making it unique among the B vitamins. Unlike some of its counterparts, which may be present in both plant and animal sources, B12 is predominantly available through dietary sources that are animal-based.

The association between B12 and folic acid also underscores their combined importance in preventing certain health issues, such as megaloblastic anemia, which can arise from deficiencies in either nutrient.