What obscured the visibility of the suspect's facial features?

The correct answer is that wearing a hat and sunglasses obscured the visibility of the suspect's facial features. This combination effectively limits visibility for onlookers and law enforcement, making it difficult to identify a suspect. Hats can cast shadows over the face, particularly the eyes, while sunglasses obstruct the view of the eyes and other critical facial characteristics. When trying to identify a person, clear visibility of the facial features is essential, and both these items serve to disguise or conceal those features effectively.

In contrast, while wearing a ski mask can obscure facial features as well, it is a more specific item often associated with concealment for nefarious purposes. Short hair does not inherently obscure facial features. Similarly, heavy makeup is generally used to enhance or alter appearance rather than to conceal identifiable features in a way that would impede recognition. Thus, the combination of a hat and sunglasses provides a broader context for obscuring visibility.