The correct answer is option 1: Quercus spp. Cork is a type of bark that is obtained from the cork oak tree, which belongs to the Quercus genus. The cork oak tree is native to the Mediterranean region and is cultivated for its bark, which is commercially valued for its use in various industries. The bark of the cork oak tree is thick and spongy, and it is harvested without damaging the tree. After harvesting, the cork bark is processed to remove impurities and to create cork products such as wine bottle stoppers, flooring, and insulation materials. Option 2, Cedrus Deodara, is incorrect because this tree species does not produce cork. Options 3 and 4, Ficus and Cycas, are also incorrect as they are not known for producing commercially valued cork.