Inheritance of skin color in humans is an example of which of the following?

Which trait in humans exhibits polygenic inheritance?

Grain colour in wheat is determined by three pairs of polygenes. Following the cross $AABBCC$ (dark colour) $\times$ $aabbcc$ (light colour),in $F_2$ generation,what proportion of the progeny is likely to resemble either parent?

The grain color in wheat is controlled by three pairs of polygenes. When a red-grained wheat variety is crossed with a white-grained variety,an $F_1$ hybrid is produced. When the $F_1$ hybrid is self-pollinated,what fraction of the $F_2$ generation will resemble the parental phenotypes?

The inheritance of skin color in humans is an example of which of the following?

It is easier to study polygenic inheritance of characters in plants than in animals because in plants: