The relevant provision belongs to the Directive Principles of State Policy (DPSP), contained in Part IV (Articles 36–51) of the Indian Constitution. These principles were borrowed from the Irish Constitution and, though non-justiciable (not enforceable in a court of law), they are described as "fundamental in the governance of the country." They act as a moral and political compass, directing the State to build a welfare society.

Article 38 is the flagship welfare directive. It commands the State to "strive to promote the welfare of the people by securing and protecting as effectively as it may a social order in which justice — social, economic and political — shall inform all the institutions of national life." A clause added by the 44th Amendment (1978) further asks the State to minimise inequalities in income, status, facilities and opportunities. Because the wording in the question — promoting welfare and securing/protecting the people "as effectively" — mirrors Article 38 almost verbatim, it is the correct answer.

The nearby Articles deal with related but distinct themes, which is why they are tempting distractors: Article 39 lists specific principles of policy such as adequate means of livelihood and equal pay for equal work; Article 40 directs the State to organise village panchayats; and Article 41 concerns the right to work, education and public assistance in cases of unemployment, old age and sickness. None of these carries the broad, umbrella welfare mandate of securing a just social order — that is uniquely Article 38.