Why can't access parent class method?

Question

typescript

export interface IProfileStaff {
  getName(): string;
}

export interface IProfilePupil {
  getName(): string;
  getOrganization(): void;

}

export class Organization { 

  protected getOrganization() { 
    return 'Organization name';
  }
}

export class ProfileBase extends Organization  { }

export class StaffProfile extends ProfileBase implements IProfileStaff {

  public getName() { 
    return '';
  }

}

export class PupilProfile extends ProfileBase implements IProfilePupil {
    public getName() { 
    return '';
  }
}

let a = new StaffProfile();
let b = new PupilProfile();
let arr: ProfileBase[] = [];

arr.push(a);
arr.push(b);

Why can't I access the getOrganization method of the Organization class
a.getOrganization(); // Здесь

Answer 1

Why can't I access the getOrganization method of the Organization class

Because it is protected: available to the class itself and its descendants. But not publicly. You can, for example, add

public getOrganization() { 
    return super.getOrganization();
  }

the ProfileBase class. Then the original will still be hidden in the Organization class, but available for calling from ProfileBase and ProfileBase descendants.