Domestic producers fear imports if the imports bring down their revenue.
Country U had many advantages in apple's production over Country C such as various varieties offered for sale, better technology to support packaging and sorting of apples, infrastructural advantages, and higher quality apples. The packing houses of Country U are able to supply high quality apples as demanded by the importing companies.
The apples of Country C on the other hand were of poor quality and were less safe in addition to high prices. Country U also expected its sales of apples to exceed its imports from Country C. Therefore, apples imported from COuntry C were not a threat to Country U's apple growers.
No, because they expected their sale of apples to exceed the imports from Country C. Country C's apples were not sold in high amounts in other countries.
However, they feared that the bad qualities of apples imported from Country C might bring in diseases and pests in Country U, which might affect Country U's harvest in the long run.