In which context would the term "unkempt" be appropriate?

The term "unkempt" is used to describe something that is disheveled, untidy, or messy. In this context, depicting a messy hairstyle directly aligns with the meaning of "unkempt," as it implies a lack of grooming or orderliness. When someone has an unkempt hairstyle, it suggests that their hair is not neatly styled or maintained, thereby highlighting the attribute of being disorderly or neglected.

The other options refer to situations characterized by tidiness or organization. Describing a well-kept garden, an organized office space, or a tidy classroom emphasizes care and maintenance, which contrasts sharply with the essence of being unkempt. Therefore, the correct understanding of "unkempt" clearly relates to the depiction of a messy hairstyle.