In Addam's Family,there Is an Autosomal Dominant Condition in Which

In Addam's family,there is an autosomal dominant condition in which webbing attaches the second toe to the third toe and the second toe is longer than the big toe.Only some of the members who have inherited the mutant allele have a second toe longer than the big toe.In addition,the extent of webbing varies.This phenotype is

A) both inherited and non-inherited.
B) dominant and recessive.
C) variably expressive and incompletely penetrant.
D) invariably expressive and completely penetrant.