Final answer:
SOSL stands for Salesforce Object Search Language. It is used for text-based search queries within Salesforce, allowing searches across multiple objects and fields.
Step-by-step explanation:
SOSL stands for Salesforce Object Search Language. It is a search language that enables you to perform text-based search queries against the search index of your Salesforce data. With SOSL, you can search across multiple objects and fields at once, which is particularly useful for implementations that require searching across large datasets and multiple objects. The correct option from your list is number 4.