Final answer:
A web page that clearly states when it was last updated is showing its 'currency', which indicates how up-to-date the information is, crucial for the reliability of certain topics.
Step-by-step explanation:
If the Web page is a good one, it will state clearly when the page was last revised or updated to show currency. The currency of a website refers to how up-to-date the information provided is. This is particularly important depending on the topic's need for current information. For example, medical or technological content requires very recent updates to be considered reliable. Additionally, checking if the links within the source are current and functional is part of verifying the website's currency.
While preparing research or gathering information, you may find the CRAAP test useful. This easy-to-remember tool stands for Currency, Relevance, Authority, Accuracy, and Purpose. It is a checklist that provides a method for evaluating any source for both reliability and credibility. In relation to the given options, currency is what is directly indicated by the date of the last revision or update of a web page.