The correct answer should be A
Premise: In any case only 2% traveller's are ever caught with restricted items
Conclusion: Better to remove restriction.
(A)The restrictions themselves do not discourage people from carrying restricted items on to airplanes.
This assumption leads to conclusion as if restriction is not discouraging people then it doesn't matter if we keep restriction or not
(B) The restrictions have been implemented all across the world.
This is too extreme.
(C) There is no scope for corrupt practices on the part of those enforcing these restrictions.
This is new information and is still extreme of totally no scope
(D) There have been instances when an innocent traveler has been wrongly detained by over cautious airline personnel.
No information regarding innocent travellers being caught or non innocent travellers
(E) Criminals are hardly likely to carry restricted items with them on an airline.
This is too extreme for criminals to be thought of 2%. It can be more and likeliness of them carrying restricted items cannot be negated as per the passage.
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