GMAT Critical Reasoning (CR) | Kernland imposes a high tariff on the export of unprocessed

Argument: removing the tariff would seriously hamper the government's effort to reduce urban unemployment over the next five years.

how to weaken the above argument?
by Proving:
tariff
=> do not reduce urban unemployment
=> increase the urban unemployment

E) A lack of profitable crops is driving an increasing number of small farmers in Kernland off their land and into the cities.
==> Because of tariff, farmers are moving to urban areas and are increasing the unemployment figures of