Step 1: Contrast with Brahmo Samaj's approach:
While Brahmo Samaj drew on universal rational religion, Arya Samaj specifically called for a return to the authority of the Vedas as the sole source of true religion, rejecting later accretions like idol worship and rigid caste.
Step 2: Highlight its distinctive activities:
Its Shuddhi movement (ritual re-conversion of Hindus who had converted to other religions) and its network of Gurukuls/DAV schools were distinctive tools it used to strengthen Hindu identity and spread education.
Final Answer:
Founded in 1875 by Swami Dayanand Saraswati, Arya Samaj reformed Hinduism through a return to Vedic teaching, opposing caste and idol worship while building schools and running the Shuddhi movement.