Correct option is D
The phrase "equal protection of the laws" is directly related to Article 14 of the Indian Constitution. Article 14 guarantees that "The State shall not deny to any person equality before the law or the equal protection of the laws within the territory of India." This principle is foundational to the right to equality under Indian law.
Article 14 permits classification but requires that it must be reasonable, based on intelligible differentia that distinguishes persons or things that are grouped together from others left out of the group, and the differentia must have a rational relation to the objective sought to be achieved by the law in question. This is how the Constitution ensures that the equal protection clause can be contextual and just rather than mechanically uniform.
Therefore, the correct answer is (d) Article 14