One of the following compensation income of an individual taxpayer is not an exclusion from gross income:
a) Monetized vacation leaves not exceeding 10 days a year.
b) Separation pay o fan employee who resigned from his employment.
c) Retirement benefits of an employee under a qualified benefit plan who has worked for an employer for at least 10 years, who at the time of retirement is not less than 50 years of age, and who avails of the retirement for the first time.
d) All of these.