C。解析:Grafting is a method of asexual reproduction in plants. It involves joining parts of two different plants together so that they grow as one. Fertilization is part of sexual reproduction. Seed dispersal is related to the spread of seeds after sexual reproduction. Cross - pollination is ...
After showing elsewhere that three of these aphid species have low dispersal and mostly if not exclusively asexual reproduction, we here investigate aphid diversity within and between ant nest mounds. Results The three focal species (Geoica utricularia, Forda marginata and Tetraneura ulmi) had consi...