Is this the Danish version for "duck or rabbit?"?
Nah, that's a picture illusion that's global. This question makes as much sense as a duck reading a newspaper
A turtle of course! Duo, I think you need new glasses if you can't see that...
They could be talking to children in swimming class groups, but I am at least a dolphin. At least they are past the starfish and tadpole stages of swimming.
Or they could ask that for which costume they're going to wear for Halloween