The World's hardest Riddle

The answer is "pressure," although some people have argued that the answer is "time" because it refers to the following poem.

Time
The time has come,
winter is here
and those yellow bears disappear.

The time has past
as man looks back with a sigh
and a tear in his eye.

As time is held
boys cross their legs
but of course the toilet begs

As time marches on
Girls loose their blush
and swap a comb for their brush

As time passes
For those held high
their end is nigh

As time catches up
Everyone is equal
when we get to the final sequel

As time turns
Without it we have flour and water
With it we have breakfast for my daughter

As time revolves
into something so fine
As time runs out
The more in a minute you try and squeeze
the less you can do with ease.

As time ticks
All the time that has past
man cannot comprehend something so vast.

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