In pea plant, B gene shows
a) Incomplete dominance wrt starch grain size
b) Complete dominance wrt seed shape
c) Pleiotropy
d) Codominance

In pea plant for example, if gene controlling the size and shape is represented with letter B, then BB combination would generate seeds with large size and round shape. Bb combination would generate seed with round shape but with intermediate size. The bb combination would generate seeds with small size and wrinkled shape. Hence gene B is incomplete dominant with respect to starch grain size, complete dominant with respect to seed shape. Hence it exhibits pleiotropy.