I Can't Read...
This is another Trump Meme. In this meme, trump is holding up a document he signed that says that he can't read.
As much as political jokes that are insulting are usually not that funny to me, this one is sort of funny because it is blatantly not true. Also, the sad face on trump is funny, because he seems to be sad that he cannot read.
It is absurd to assume that an adult human in America is illiterate, and that the president of the US might be illiterate is even more funny. It would be quite unexpected.