Education
A measurable enquiry channel, and a brand.

Education marketing is judged on enquiries, and enquiries are only useful if you can tell where they came from and what happened next. Dimension needed both the brand and the plumbing.
This is the second widest scope on the list. Paid media, email and telemarketing feed a CRM the enquiries land in, so the review at the end of a month is a comparison rather than an argument.