Final answer:
Analyzing Neanderthal DNA has revealed a genetic predisposition to certain diseases (option A) and provided clues about skin and hair color (option C), but not directly about dietary habits or language abilities, which are inferred from other types of evidence.
Step-by-step explanation:
Scientists have discovered a range of insights from Neanderthal DNA, including evidence of a genetic predisposition to certain diseases, and indications of skin and hair color. However, discoveries about Neanderthal dietary habits or language abilities come from archaeological and paleontological evidence rather than genetic data. For instance, studies have shown that certain Neanderthal DNA segments may increase the risk of disease in modern humans due to lifestyle and environmental changes. Additionally, Neanderthal genes affecting immune responses can be linked to allergies and autoimmune disorders, while others may offer some protection or increased risk concerning modern-day ailments like COVID-19.