The answer is B: Because authors and indexers may use multiple terms for the same topic.
Explanation for each option:
A. Each database record is required to use different terms for the same topic - This is incorrect. While different records might use different terms, there is no requirement for each database record to use different terms for the same topic. The variation in terms is due to the diversity in language used by different authors and indexers.
B. Because authors and indexers may use multiple terms for the same topic - This is correct. Different authors and indexers might use various synonyms or related terms to describe the same concept. Having a list of synonyms ensures that you can capture all relevant records, regardless of the specific terminology used.
C. Databases limit the keywords you can use - This is incorrect. Databases typically do not limit the keywords you can use; rather, they allow you to use a wide range of terms to refine and expand your search.
D. You can search for more articles in Google than in a database - This is incorrect. While Google may have a broader range of articles, the reason for using synonyms in a database search is not related to the number of articles available but to ensure comprehensive coverage of the topic within the database.
In summary, using synonyms in database searches is important to account for the variability in language used by different authors and indexers, ensuring a more comprehensive search result.