Which function correctly calculates the smallest possible number of employees in a binary tree hierarchical data structure representing a company's organizational chart?

Note: This is a Multi-Select question. Choose all that apply. C] Python 1 def min_employees(levels): 2 it levels == 3 return 1 4 elif levels == 1: 5 return 2 5 else: 7 return 1 + 2 + min_employees(levels - 1) Python 1 def min_employees(levels): 2 it levels == 3 return 1 4 else: 5 return 1 + min_employees(levels) O Python 1 def min_employees (levels ) : 2 if levels = = 0: W return 1 4 else : 5 return 1 + min_employees (levels - 1) O Python 1 def min_employees (levels ) : 2 if levels == 0: 3 return 1 elif levels == 1: return 2 else : return 1 + min_employees(levels - 1)