How should you advise an advertiser to do a bulk creatives upload in Display & Video 360?

Use a spreadsheet template or structured data file.
Use a spreadsheet or the Display & Video 360 API, as you can’t upload creatives directly into Display & Video 360.
Use a spreadsheet template, Display & Video 360 API, or upload the creatives directly to DV360.
Upload the creatives directly into Display & Video 360.