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18. Ethical arguments against the cloning of humans include:
a) cloning using differentiated cells might cause suffering because it carries a high risk of fetal abnormalities and a high rate of miscarriage.
b) cells have an internal age clock. Differentiated cells from older donors may result in human clones that may grow older more quickly than normal.
c) If a large number of genetically identical people are created, they may suffer from psychological problems of identity or individuality.
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