The argument has a reasoning gap where why the basis is ill founded has to be answered.
Between A and C.
C Means there was a competition between a bigger store and the smaller store.Now because of the competition the smaller store failed.However,with time the bigger store found the business to be non profitable and hence it withdrew those products from its business.Thus,business taking over same products and places flourished.
This can be one of the possible reasoning. However, as you can see there is plenty of assumption being done here.
A Anchor store means important stores upon which other businesses are depended.If such Anchor stores fail,other businesses will vanish to the point of non return. Hence this choice gives a clear reasoning,as its visible.
Hence A is a better choice.
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