In which scenario could you use adjacent feature attributes?

• A. You need to filter out expired contracts from a list of contracts, where each contract is a feature containing an expiry date attribute.
• B. You have park features, each with a numerical attribute reporting the annual visitor count. You need to find the average visitor count.
• C. You have a text file that records monthly visitors to a website. You need to find out the increase (or decrease) in visitors each month.
• D. You need to find the closest hospital to a given location.

Answer: (C)

Adjacent feature attributes are used when you need to compare a feature’s value to the value of a neighboring feature in a sequence, such as the previous or next item in a time-ordered set. For monthly website visitors, finding the increase or decrease from one month to the next requires grabbing the prior month’s visitor count and subtracting it from the current month’s count. This is exactly what adjacent attributes enable: you access the adjacent (previous) feature’s attribute to compute the change month over month, after ordering by date.

The other scenarios don’t rely on comparing neighboring features. Filtering expired contracts is a straightforward attribute-based filter. Computing an average is an aggregation across features, not a comparison to a neighbor. Finding the closest hospital is a spatial proximity task, not about adjacent attribute values.