I'm beginning to see a pattern emerging here.
When I googled "softest allotrope of carbon", several of the results were the same as the ones that came up when I googled "brass discoloured hydrogen sulphide" (four questions ago). Here's an example from examveda.com ("Our mission is to make digital education reachable to everyone"):
Among the various allotrope (sic) of carbon ...
A. Coke is the hardest, graphite is the softest
B. Diamond is the hardest, coke is the softest
C. Diamond is the hardest, graphite is the softest
D. Diamond is the hardest, lamp black is the softest
The correct answer is C: diamond is the hardest, graphite is the softest.
Some of the other sites that came up in both searches were eanswers.com and indiabix.com.
Not that there's anything really wrong with that; except that it smacks of someone trolling the Internet for questions that they don't really know anything about. And I'm not convinced that their source knows much more.
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