SObjects-ParentII.cls

/*
Implement the method sameParent that takes as input an account acc, a contact con, and an opportunity opp and returns true if both the opportunity and contact have the given account as the parent.

Given the following test code:

Account acc = new Account(Id = '0018c00002CQU9EAAX');
Contact con = new Contact(AccountId = acc.Id);
Opportunity opp = new Opportunity(AccountId = acc.Id);
The method call sameParent(acc, con, opp) returns true because both the contact and the opportunity have the same parent account.
*/
public Boolean sameParent(Account acc, Contact con, Opportunity opp) {
    //code here
    if(acc.Id == con.AccountId && con.AccountId == opp.AccountId && con.AccountId != null && opp.AccountId != null){
        return True;
    }
    return False;
}