Polygenic inheritance is observed in which of the following?

In human beings,multiple genes are involved in the inheritance of

In a plant,the weight of fruits is determined by the number of dominant alleles for several genes. If seven categories of weight are obtained,how many loci are involved in this trait?

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?

Polygenic traits exhibit $....$.

In a dihybrid cross,instead of a $9:3:3:1$ ratio,a $1:4:6:4:1$ ratio is obtained. This is an example of .....