Answer:
yes, a person must inherit two copies of the gene for it to be expressed.
Step-by-step explanation:
Having a hitchhiker's thumb is a genetic trait that is passed down from parents to their children. An individual must inherit two copies of the gene for it to be expressed.
This means that if one parent has a hitchhiker's thumb and the other parent does not, their children will not necessarily have the trait, but may inherit one copy of the gene for the trait. If both parents have a hitchhiker's thumb, their children are more likely to have the trait.