An email marketer wants to exclude Gmail addresses; how could they fix the filtering condition written?

To exclude Gmail addresses effectively, it is essential to understand how filtering conditions work in the context of an email marketing campaign. When the filter condition is set to "is empty," it implies that the specified field has no value at all. However, to proceed with excluding Gmail addresses, the right approach would be to specify that the Gmail addresses exist or are not the ones to include.

By changing the condition from "is empty" to "is not empty," the filter becomes focused on identifying records that have an email address present and, in this context, allows for more precise exclusions. This means that the marketer can ensure the records being processed in the campaign do not include any Gmail addresses, thereby achieving the desired exclusion.

In contrast, the other options do not align with the necessity to exclude Gmail addresses effectively. Adjusting conditions with words like "except" or "or," or altering "is null" would not provide the appropriate specificity needed to specifically exclude Gmail users. Thus, the modification towards "is not empty" serves the intended purpose by narrowing down the candidate list to only those addresses that do not meet the Gmail criteria.