Objects in the image:
category: surfboard
category: surfboard
category: person
category: person
category: surfboard
category: surfboard
category: person
category: person
category: person
category: person
category: surfboard
category: person

Guessing-game dialogue about one of the objects:
q: is it a person?
a: Yes
q: is it one of the four walking in the front?
a: Yes
q: is the person wearing green?
a: No
q: is he wearing blue?
a: Yes