Find the missing square, options are at the bottom.
This is not your typical "IQ test" question.
The answer is
The fourth square (50).
This question is a reference to
The Loss meme.
Each number, when written in Roman numerals, corresponds to the position of the humans in its respective panel in the comic. The lines correspond to non-human elements in the pictures.
This is the answer because
50 is "L" in Roman numerals, with the comic having one person standing and one person lying in bed in its final panel - with the bed showing in the answer as the horizontal line.