In this challenge you need to use the idea of falsy instead of trying to search for some special values to remove. A value is falsy if it “acts like” false when used as a logical condition:
if (NaN)
console.log("NaN is *not* falsy!");
I wouldn’t look at anything that compares a value to NaN or any other particularly falsy value.
I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.
You can also use the “preformatted text” tool in the editor (</>) to add backticks around text.
See this post to find the backtick on your keyboard.
Note: Backticks (`) are not single quotes (’).