humor - The case of the world’s easiest puzzles

   Welcome back, my friends, to the show that never ends.   We’ re so glad you could attend,
   Come inside, come inside.
   Step inside, hello! We’ ve the least amazing show.   You’ ll enjoy it some, we know,
   Step inside, step inside.

   Rest assured, you’ ll get your money’s worth.   Easiest puzzles in Heaven or Hell or on Earth.
   If you follow me, to our speciality, real gimmes for you to see,
   Simplicity, simplicity.    — adapted from Karn Evil 9 _YouTube by Emerson, Lake & Palmer

Step right up to our traveling display case and be dumbstruck by the easiest puzzles you’ll ever see.

These abysmal abominations are so mind-numbingly vapid that we cannot even expose them to air, or they will spontaneously burst into solutions.   Ooo, you could swoon abashedly. Or you could shed all dignity and dare imagine just what it would be like to try and actually solve such crude puzzles, if permitted, quicker than they solve themselves.   Or, you could answer...

             What might each puzzle be anyway?

For instance, the first puzzle might be (though you should think of another)...

  a. World’s easiest paperfolding puzzle:   Divide into two areas by folding the fewest possible times.

Puzzle h has the special condition that its answer cannot also suit puzzle e.   Thus Knight’s Tour, for example, could be an answer only for puzzle e, which would be a 1×1 chessboard with a single white square, even though puzzle h could be perceived as an equivalent black square.

Only puzzles h, i and j are meant to be at all challenging to identify, the rest intended as warm-ups with room for playfulness. Some, certainly puzzle e, can represent countless of the world’s easiest puzzles.   Each puzzle is meant not only as the world’s easiest but also as the simplest, so special instructions should be minimal, or else some simpler puzzle is more likely the one represented.

$\small\sf\color{black}{Hints \! :}$   Some specimens are displayed at deliberately misleading scales.
    One of these sideshow geeks has a family member locked in The trunk of trivial trials.

Easier/simpler/additional samples, as improvements or new mysteries, are more than welcome!

Answer

Possible answers for the non starred ones:

a.

Symmetry puzzle: Fill in one square so the entire sheet has two lines of symmetry.

You

Fill in the middle square

b.

Its Haisu!

So

Draw a line through every cell from O to X

c.

Alphametic

So

What number could Z be? (Answer 0)

d.

Match puzzle: Move the match once to create a vertical line

e.

Division puzzle: Split the square into two triangles with one line (just draw a diagonal)

f

Its a cryptic clue

So

What the answer? (It's I)

g

Looks like tower of Hanoi

So

How many moves does it take to get the ring from L to R?

Now for the starred ones:

h

Could be a chess puzzle: How many squares can a knight reach from this square (0 as it's the only square)

It was actually:

A crossword. Solved by Gareth.

i

How about a keyboard puzzle? What other symbol is on this key on your keyboard (Answer +)

It was actually:

A maze. Solved by KeyboardWielder

j

Seems like a rebus. Don't know what it could be for though

Or (thanks @Silenus)

It is representative of a Droste effect of a puzzle in a puzzle in a puzzle

It was actually

Puzzle identification. Solved by Marius.