What is a major environmental consequence of lead contamination in water?

Lead contamination in water poses significant health risks to both humans and wildlife, making this option the most accurate choice. Lead is a toxic heavy metal that can have serious implications when it enters the human body or that of animals. For humans, exposure to lead can result in a range of health problems, including neurological damage, reproductive issues, and developmental delays in children. Wildlife can also suffer detrimental effects, affecting growth, reproduction, and overall survival.

The other options present environmental consequences that do not align with the characteristics of lead. For instance, lead does not promote the growth of algae, which is typically related to nutrients like nitrogen and phosphorus. Additionally, lead contamination does not lead to a decrease in water temperature or an improvement in aquatic biodiversity; rather, it can be detrimental to aquatic ecosystems, often leading to reduced biodiversity as sensitive species are affected by the toxic nature of lead.