Given observations of a family, identify the best-supported conclusion about genetic versus environmental trait determination.
A. A child develops early-onset cataracts that the maternal grandmother also developed, and O both individuals were delivered in the same hospital. Conclusion: environmental factors caused the cataracts B. Non-identical siblings with intact hearing are the biological offspring of parents who are deaf. Conclusion: environmental factors caused deafness in the parents Identical twins separated at birth and raised in different parts of the country both have a O severe form of asthma that neither biological parent has. Conclusion: genetic factors caused the asthma C. Identical twins raised by their biological parents both have a specific congenital heart O defect that neither parent has. Conclusion: environmental factors caused the congenital heart defects D. Among non-identical siblings, one sibling was prenatally exposed to a known teratogen and born with birth defects. Conclusion: genetic factors caused the birth defects
