ISO 26000 is: 

a. A voluntary social responsibility guide that tries to protect organizations on their path towards sustainability, covering environmental, social and legal frameworks, therefore it is not certifiable. 

b. A social responsibility ordinance that tries to guard organizations on their path towards sustainability, covering environmental, social and legal frameworks, which is why its certification is mandatory. 

c. An enforceable standard of social responsibility that seeks to protect organizations on their path towards sustainability, encompassing the environmental, social and legal frameworks, which is why its certification is mandatory. 

d. A social responsibility guide that tries to adjust organizations on their path towards economic sustainability, covering environmental, social and legal frameworks, which is why its certification is voluntary.