I felt this to be a great question.

But a little time taking.

say 1000 total accidents occured.

100 of them S.Injured .

80 --> X seat belt.

20 ---> Seat belt.

Now,

Option A: for suppose its exactly 20% of people wore seat belt.

20 / 200 = 10% of accidents of seat belt are SI .

80 / 800 = 10 % of accidents of X Seat belt are SI

For suppose, it is less than 20% of people wore seat belt.

% of accidents of seat belt are SI Increases as 200 value increases while 20 remains constant.

Destroying the conclusion .

Hence, Answer should be A.

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