Question

2 which of the following is a limitation of twin studies? a. the studies are not reliable. b. it is difficult to find samples. c. the samples are not representative. d. it is not possible to really know if a twin is monozygotic or dizygotic

Explanation:

Twin studies are a well-established reliable method, so A is incorrect. While twin samples require targeted recruitment, they are not inherently difficult to find, so B is wrong. Genetic testing can accurately distinguish monozygotic (identical) and dizygotic (fraternal) twins, so D is incorrect. A key limitation is that twin populations (especially those raised together) may not reflect the general population, making samples non-representative.

Answer:

C. The samples are not representative.