The correct answer is option 4, Ignatius Loyola. The Society of Jesus, commonly known as the Jesuits, was founded by Ignatius Loyola in the year 1540. Ignatius Loyola was a Spanish nobleman and devout Christian who became a priest and later founded the Jesuit order.

Option 1, Martin Luther, is incorrect. Martin Luther was a German theologian and key figure in the Protestant Reformation, but he did not establish the Jesuits.

Option 2, Ulrich Zwingli, is also incorrect. Zwingli was a Swiss priest and leader of the Reformed Church in Switzerland, but he was not involved in the founding of the Jesuits.

Option 3, Erasmus, is incorrect. Erasmus was a Dutch humanist and scholar who played a significant role in the development of Renaissance thought, but he did not establish the Jesuits.

In conclusion, it was Ignatius Loyola who established the Society of Jesus and its followers, known as Jesuits.