Given the task definition, example input & output, solve the new input case.
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.
Example: Passage: The French and Indian War (1754–1763) was the North American theater of the worldwide Seven Years' War. The war was fought between the colonies of British America and New France, with both sides supported by military units from their parent countries of Great Britain and France, as well as Native American allies. At the start of the war, the French North American colonies had a population of roughly 60,000 European settlers, compared with 2 million in the British North American colonies. The outnumbered French particularly depended on the Indians. Long in conflict, the metropole nations declared war on each other in 1756, escalating the war from a regional affair into an intercontinental conflict.
Output: When was the French and Indian War?
This question is based on the following sentence in the passage- The French and Indian War (1754–1763) was the North American theater of the worldwide Seven Years' War. It is a common convention to write (start year-end year) beside a historical event to understand when the event happened. You can ask questions like this one about dates, years, other numerals, persons, locations, noun phrases, verb phrases, adjectives, clauses etc. which exist in the paragraph.

New input case for you: Immigration to Israel during the late 1940s and early 1950s was aided by the Israeli Immigration Department and the non-government sponsored Mossad LeAliyah Bet ("Institution for Illegal Immigration"). Both groups facilitated regular immigration logistics like arranging transportation, but the latter also engaged in clandestine operations in countries, particularly in the Middle East and Eastern Europe, where the lives of Jews were believed to be in danger and exit from those places was difficult. Mossad LeAliyah Bet continued to take part in immigration efforts until its disbanding in 1953. An influx of Holocaust survivors and Jews from Arab and Muslim lands immigrated to Israel during the first 3 years and the number of Jews increased from 700,000 to 1,400,000, many of whom faced persecution in their original countries. The immigration was in accordance with the One Million Plan.
Output:
Who aided the immigration to Israel?