Should be set as a cover. This photo has class "main_single_img", other photos haven't any classes, so Following The Checklist, ch .6.2.2:
6.2.2 Cover images It is obligatory to use a cover image: - If the image is present on the page and described in the source as “featured-img”, “cover”, “lead_img”, “main_image”, etc.
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This photo has class "main_single_img", other photos haven't any classes, so
Following The Checklist, ch .6.2.2:
6.2.2 Cover images
It is obligatory to use a cover image:
- If the image is present on the page and described in the source as “featured-img”, “cover”, “lead_img”, “main_image”, etc.