Sentence Correction

Data collected from various sources indicate that [in any given year, 2000 people should be struck by lightning], while approximately 30% of those struck will die.

A) in any given year, 2000 people should be struck by lightning
B) 2000 people should be struck by lightning in any given year
C) lightning will strike human beings 2000 times per year
D) each year, 2000 people will be struck by lightning
E) each year, lightning should strike 2000 times

Answer is D

The explanation from KAPLAN says something about usage of Will and Should in this sentence (e.g. should = ought) but to be honest I do not understand it. Could someone help?[/u][/b]

Milovan,

Should is used where there is "an obligation"

Will when you are predicting or expecting something to happen.

E.g
A bike should be washed regularly to prevent it from rust. (obligation)
We expect that train will get delayed. (prediction)