Final answer:
In Splunk, continuous monitoring of files is best achieved through real-time indexing, which provides immediate insights as data arrives into the system.
Step-by-step explanation:
To continually monitor files in Splunk, one would generally use the real-time indexing feature. This Splunk capability allows you to monitor and analyze data as it comes into the system, providing immediate insights and alerts. While scheduled searches can be helpful for recurrent analysis of data, real-time indexing is specifically designed for continuous monitoring. Batch processing is more related to processing large volumes of data at once, and historical queries are for analyzing data that's already been indexed.