Answer based on context:

Sizable Lutheran missions arose for the first time during the 19th century. Early missionary attempts during the century after the Reformation did not succeed. However, European traders brought Lutheranism to Africa beginning in the 17th century as they settled along the coasts. During the first half of the 19th century, missionary activity in Africa expanded, including preaching by missionaries, translation of the Bible, and education. Lutheranism came to India beginning with the work of Bartholomäus Ziegenbalg, where a community totaling several thousand developed, complete with their own translation of the Bible, catechism, their own hymnal, and system of Lutheran schools. In the 1840s, this church experienced a revival through the work of the Leipzig Mission, including Karl Graul. After German missionaries were expelled in 1914, Lutherans in India became entirely autonomous, yet preserved their Lutheran character. In recent years India has relaxed its anti-religious conversion laws, allowing a resurgence in missionary work. In Latin America, missions began to serve European immigrants of Lutheran background, both those who spoke German and those who no longer did. These churches in turn began to evangelize those in their areas who were not of European background, including indigenous peoples. In 1892, the first Lutheran missionaries reached Japan. Although work began slowly and a major setback occurred during the hardships of WWII. Lutheranism there has survived and become self-sustaining. After missionaries to China, including those of the Lutheran Church of China, were expelled, they began ministry in Taiwan and Hong Kong, the latter which became a center of Lutheranism in Asia. The Lutheran Mission in New Guinea, though founded only in 1953, became the largest Lutheran mission in the world in only several decades. Through the work of native lay evangelists, many tribes of diverse languages were reached with the Gospel.

How many factors were involved in the missionary activity of the 19th century in Africa?
3