在发生转化事件时，下面哪一项 Floodlight 功能可用于衡量网页上的特定元素？

Custom variables (自定义变量) in Campaign Manager 360 are used to capture specific, dynamic information about a conversion event that occurs on a webpage. They allow you to pass custom data, such as product IDs, order values, or user types, from your website to Floodlight when a conversion happens. This enables more granular reporting and analysis beyond standard Floodlight data. Custom dimensions (自定义维度) are typically used in analytics platforms to categorize data, not directly for capturing dynamic event data in Floodlight. Custom parameters (自定义参数) is a general term and not the specific Floodlight feature for this purpose. Custom attributes (自定义属性) are often associated with user profiles or other data management platforms, not directly with Floodlight event tracking.