Final answer:
The question is about identifying valid tagged custom campaigns used for tracking marketing efforts. Options b, c, and d are valid because they correctly use UTM parameters. Option a contains a typographical error, making it the invalid option.
Step-by-step explanation:
The question asks which of the following is a valid tagged custom campaign for tracking marketing efforts and visitor behavior through URL parameters. URL parameters, often called UTM parameters, allow marketers to track the effectiveness of online marketing campaigns across traffic sources and publishing media.
Each option given contains different combinations of UTM parameters such as utm_medium, utm_source, utm_campaign, utm_term, and utm_content. The UTM parameters must be correctly formatted, with each parameter separated by an ampersand (&) and using an equals sign (=) to assign value to each parameter. Additionally, an initial question mark is used to start the query string in the URL.
While all options might seem valid at a glance, option a has a typographical error where the utm_campaign parameter is incorrectly joined to its value with a hyphen instead of an equals sign. Therefore, the valid tagged custom campaigns would be b, c, and d.