This explanation is posted before the OA is released.
"When an adult was present in the room, the children were more likely to share the toys with their siblings than with non-siblings." And the conclusion derived from this is that, in presence of adults, children prefer sharing toys with siblings to sharing with non-siblings.
A: the toys in the room were new to children, rather than toys they had previously played with at home.
This weakens the conclusion, the children might have shared the toys merely because they were new to them, the 'look what I found' phenomenon.
B. the observing adult was a parent of the siblings, rather than a stranger or non relative adult.
This also weakens the conclusion by limiting the observation conditions which derived a general conclusion relating to all adults/ authority figures.
C. the siblings were younger and appeared to need help understanding how to use the toys, compared to non-siblings who were adept at using the toys.
This weakens the sharing hypotheses/ conclusion drawn, if the children were only seen to be sharing while they might have actually been helping their siblings out.
D. the room had more toys available than usual, making it easier for children to find and share multiple toys.
This weakens the conclusion, if children had more options to play with, they may find it easy to share the toy with their siblings that they have already played with.
E. the adult explicitly encouraged the children to share, regardless of whether the other child was a sibling or a non-sibling.
This does not weaken the conclusion, and might strengthen it, if the adult encouraged the children to share with others and they shared it only with their siblings still, supports the conclusion that children are more inclined to share with family members.
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