The correct answer is option 3: an Act passed by the Parliament. The National Commission for Women (NCW) was established through an Act of the Indian Parliament called the National Commission for Women Act, 1990. This act was passed to address the issues and concerns of women and to promote their rights and entitlements.

Option 1 suggests that the commission was created through an amendment in the 117th Constitution of India. However, this is not correct as the NCW was established through a separate act and not through a constitutional amendment.

Option 2 suggests that the commission was created through a decision of the Union Cabinet. While it is possible for the Union Cabinet to take decisions related to the functioning of the NCW, the commission itself was established through an act passed by the Parliament.

Option 4 suggests that the commission was created through an order of the President of India. However, this is not correct as the NCW was established through an act passed by the Parliament and not through a presidential order.

In conclusion, the correct answer is option 3 as the National Commission for Women was created by an Act passed by the Parliament.