const company = {
  name: "TechCorp",
  ceo: {
    name: "Morgan",
    address: {
      city: "Berlin"
    }
  },
  getRevenue: () => 5_000_000
};

const cfoCity    = company?.cfo?.address?.city ?? "Unknown";
const ceoCity    = company?.ceo?.address?.city ?? "Unknown";
const ceoCountry = company?.ceo?.address?.country ?? "N/A";
const revenue    = company?.getRevenue?.() ?? 0;
const employees  = company?.getEmployees?.() ?? "No data";

console.log(cfoCity, ceoCity, ceoCountry, revenue, employees);