AI solution for JavaScript Quiz on BFE.dev
40. RegExp.prototype.test

The code outputs:

true
true
false
false

This is because the regular expression ^4\d\d$ matches any 3-digit number that starts with 4. The first two console.log statements test strings and numbers that match this pattern and therefore return true. However, the last two console.log statements test arrays, which do not match the pattern, and therefore return false.