Which operation counts the number of elements in a list attribute per feature?

• A. ListBuilder
• B. ListElementCounter
• C. ListSummer
• D. ListSearcher

Answer: (B)

Counting how many items are present in a list attribute for each feature is exactly what a ListElementCounter does. In FME, features can carry attributes that are lists (multivalued values). When you need to know the size of that list, you use ListElementCounter to produce a numeric count for each feature, often storing it in a new or existing numeric attribute. This enables you to gate downstream processing or analytics on how many elements a feature has.

Why this one fits best: the other transformers perform different list operations. ListBuilder creates a list from inputs, not a count. ListSummer adds up the numeric values inside a list, producing a sum. ListSearcher looks for a specific item within a list and returns its position or a flag, not the total count.