Blank verse is unrhymed iambic pentameter.
So statement A is correct.
Statement B is incorrect because blank verse is not rhymed.
Statement C is correct because blank verse has unrhymed lines.
Statement D is correct because John Milton used blank verse in Paradise Lost.
Statement E is also correct because blank verse is called blank due to the absence of rhyme.
Therefore, the correct statements are:
\[
A,\ C,\ D,\ E.
\]
Hence, the correct answer is option (C).