Alex Rider is a title character and the protagonist of the popular "Alex Rider" novel series by British author Anthony Horowitz. He has also been featured in three short stories written by Horowitz based in the same canon as the series; "", "" and "".
Can we infer the following?
The Alex Rider series has four books.

Select from the following.
+Yes;
+It's impossible to say;
+No;
The answer is:
It's impossible to say