According to the UiPath documentation, data labeling is a process that involves uploading raw data, annotating text data in the labeling tool, and using the labeled data to train ML models1. Data labeling is performed by human labelers, who can be either internal or external to the organization2. However, concurrent labeling is not supported by the UiPath Data Labeling tool, which means that only one user can label a document at a time3. If multiple users try to label the same document concurrently, they will encounter an error message that says “The document is locked by another user. Please try again later.”. Therefore, the correct answer is C.

References:

1: About Data Labeling 2: Data Labeling Roles 3: Data Labeling Limitations : Data Labeling Error Messages