"Identical twins are more similar on the trait than fraternal twins" would lead to the conclusion that genetic factors are important in the development of this trait.
Option: C
Explanation:
Research performed on identical or fraternal twins are twin investigations. We seek to expose the significance for characteristics, phenotypes and diseases of environmental and genetic factors. Twin work is considered a key instrument in the domains of behavioral genetics and material, from biology to psychology.
Fraternal or dizygous twins each share around 50 % of their DNA, just like any other parent. Since the twins are born into the same family they share other factors of their surroundings. The existence of a given genetic or phenotypic trait in just one component of a pair of twins called discordance offers a valuable insight into influence on such a trait on climate.