Given the task definition and input, reply with output. 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.

Protestants reject the Roman Catholic Church's doctrine that it is the one true church, believing in the invisible church, which consists of all who profess faith in Jesus Christ. Some Protestant denominations are less accepting of other denominations, and the basic orthodoxy of some is questioned by most of the others. Individual denominations also have formed over very subtle theological differences. Other denominations are simply regional or ethnic expressions of the same beliefs. Because the five solas are the main tenets of the Protestant faith, non-denominational groups and organizations are also considered Protestant.
What type of church do Protestants believe in?