Explanation:

Guru Gobind Singh Ji (Correct): The Khalsa was formally instituted by Guru Gobind Singh Ji, the tenth Sikh Guru, on Vaisakhi in 1699 at Anandpur Sahib. He initiated the Panj Pyare (the Five Beloved Ones) and gave them the distinctive Khalsa identity, including the Five Ks, transforming the Sikh community into a disciplined warrior-saint order to defend their faith and uphold justice against oppression. Guru Arjan Dev Ji: He was the fifth Sikh Guru (1563–1606) who compiled the Adi Granth but did not establish the Khalsa. Guru Teg Bahadur Ji: He was the ninth Sikh Guru (1621–1675) who sacrificed his life for religious freedom but did not establish the Khalsa. Guru Hargobind Ji: He was the sixth Sikh Guru (1595–1644) who introduced the concept of Miri Piri and began the militarization of the Sikhs, but the formal establishment of the Khalsa was by Guru Gobind Singh Ji.