When enabling email headers in a conceptual index, what is the outcome regarding the subject line?

When email headers are enabled in a conceptual index, the correct outcome is that the subject line content is preserved. This means that the original subject line from the emails is retained and can be utilized for indexing and search purposes. By keeping the subject line, users can maintain the context of the email, which is vital for understanding the content and relevance of the communication.

Retention of the subject line enhances the utility of the index by allowing users to make more informed decisions during searches and when sifting through email content. This is particularly important in scenarios such as eDiscovery or content review, where understanding the context provided by the subject line can aid in identifying pertinent information quickly.

The other outcomes indicate alterations or removals of the original subject line, which would hinder the effectiveness of searching and indexing the content accurately, thus making option C the best fit in preserving the integrity and utility of email data.