Having trouble with this sentence

[zerobit]

Could somebody please help me this:

There will be an increase in tax for those earning in _______ of twice the national average wage.

1) trouble
2) decrease
3) excess
4) effect

I'm having trouble in understanding what it's trying to say and can't choose between 3 and 4.

Thanks in advance

[Allen165]

3 is the right answer, and it means earning more than twice the national average wage.

I'm not a teacher.

[mmasny]

The sentence is to mean "There will be increase in tax for those earning more than twice the national average wage."
edit: sorry for doubling