how can we say that a child has two version of trait - Science - Heredity and Evolution

Question

how can we say that a child has two version of trait

Summaiyya Khan · Accepted Answer

Child inherit half set of chromosomes
from the mother and half set of chromosomes from the father Child
inherit a particular trait from both the parents For example, a
gene for tallness will have two alleles coming one from the father
and one from the mother