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.

Let me give you an 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.
The answer to this example can be: When was the French and Indian War?
Here is why: 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.

OK. solve this:
Prior to the Reformation, the Polish nobility were mostly either Roman Catholic or Orthodox with a small group of Muslims. Many families, however, soon adopted the Reformed faiths. After the Counter-Reformation, when the Roman Catholic Church regained power in Poland, the nobility became almost exclusively Catholic, despite the fact that Roman Catholicism was not the majority religion in Commonwealth (the Catholic and Orthodox churches each accounted for some 40% of all citizens population, with the remaining 20% being Jews or members of Protestant denominations). In the 18th century, many followers of Jacob Frank joined the ranks of Jewish-descended Polish gentry. Although Jewish religion wasn't usually a pretext to block or deprive of noble status, some laws favoured religious conversion from Judaism to Christianity (see: Neophyte) by rewarding it with ennoblement.
Answer:
What two religions were most common?