Answer the question from the given passage. Your answer should be directly extracted from the passage, and it should be a single entity, name, or number, not a sentence.

Let me give you an example: Passage: Martin Luther married Katharina von Bora, one of 12 nuns he had helped escape from the Nimbschen Cistercian convent in April 1523, when he arranged for them to be smuggled out in herring barrels. Suddenly, and while I was occupied with far different thoughts, he wrote to Wenceslaus Link, “the Lord has plunged me into marriage. At the time of their marriage, Katharina was 26 years old and Luther was 41 years old. Question: In a letter who did Luther credit for his union with Katharina?
The answer to this example can be: the Lord
Here is why: The paragraph clearly states that, Luther has credited the Lord for his union with Katharina, hence the Lord is correct answer.

OK. solve this:
Passage: While studying law and philosophy in England and Germany, Iqbal became a member of the London branch of the All India Muslim League. He came back to Lahore in 1908. While dividing his time between law practice and philosophical poetry, Iqbal had remained active in the Muslim League. He did not support Indian involvement in World War I and remained in close touch with Muslim political leaders such as Muhammad Ali Johar and Muhammad Ali Jinnah. He was a critic of the mainstream Indian nationalist and secularist Indian National Congress. Iqbal's seven English lectures were published by Oxford University press in 1934 in a book titled The Reconstruction of Religious Thought in Islam. These lectures dwell on the role of Islam as a religion as well as a political and legal philosophy in the modern age. Question: What organization did Iqbal join in London?
Answer:
All India Muslim League