Detailed Instructions: This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
Q: Modern Ottoman studies think that the change in relations between the Ottoman Turks and central Europe was caused by the opening of the new sea routes. It is possible to see the decline in the significance of the land routes to the East as Western Europe opened the ocean routes that bypassed the Middle East and Mediterranean as parallel to the decline of the Ottoman Empire itself. The Anglo-Ottoman Treaty, also known as the Treaty of Balta Liman that opened the Ottoman markets directly to English and French competitors, would be seen as one of the staging posts along this development.
A:
What is believed to have caused the opening of new sea routes during the Ottoman Empire?