Q:Information: - The tangerine ("Citrus tangerina") is an orange-colored citrus fruit that is closely related to, or possibly a type of, mandarin orange ("Citrus reticulata"). - The Fairchild tangerine is a bigeneric cross between a Clementine mandarin and an Orlando tangelo . The skin is thin with a deep orange color , is somewhat pebbly , and does n't peel as easily as some other tangerines . It is juicy with a rich and sweet flavour and contains seeds . It is a popular variety in the United States , available from October until the middle of January and especially during the winter holidays . The Fairchild tangerine is one of California 's most heavily planted varieties . Fairchild tangerines are sometimes found with the stem and leaves still attached . The Chinese believe the stems and leaves attached to the tangerine are a symbol of prosperity and good luck . - Citrus is a genus of flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including important crops like oranges, lemons, grapefruit, pomelo and limes. - The mandarin orange ('), also known as the robson, is a small citrus tree with fruit resembling other oranges. - In botany, a fruit is the seed-bearing structure in flowering plants (also known as angiosperms) formed from the ovary after flowering. Given the information, choose the subject and object entities that have the relation of 'instance of'.
A:
fairchild tangerine , citrus