Problem: In response to a given problem situation (), a number of competing conjectures, or tentative theories (), are systematically subjected to the most rigorous attempts at falsification possible. This process, error elimination (), performs a similar function for science that natural selection performs for biological evolution. Theories that better survive the process of refutation are not more true, but rather, more "fit"—in other words, more applicable to the problem situation at hand (). Consequently, just as a species' biological fitness does not ensure continued survival, neither does rigorous testing protect a scientific theory from refutation in the future. Yet, as it appears that the engine of biological evolution has, over many generations, produced adaptive traits equipped to deal with more and more complex problems of survival, likewise, the evolution of theories through the scientific method may, in Popper's view, reflect a certain type of progress: toward more and more interesting problems (). For Popper, it is in the interplay between the tentative theories (conjectures) and error elimination (refutation) that scientific knowledge advances toward greater and greater problems; in a process very much akin to the interplay between genetic variation and natural selection.
Toward what does Popper believe scientific understandings progress?
The answer is the following: more and more interesting problems

Problem: The uneasy alliance of Carranza, Obregón, Villa, and Zapata eventually led the rebels to victory. The fight against Huerta formally ended on August 15, 1914, when Álvaro Obregón signed a number of treaties in Teoloyucan in which the last of Huerta's forces surrendered to him and recognized the constitutional government. On August 20, 1914, Carranza made a triumphal entry into Mexico City. Carranza (supported by Obregón) was now the strongest candidate to fill the power vacuum and set himself up as head of the new government. This government successfully printed money, passed laws, etc.
In which city did Obregon sign a number of treaties?
The answer is the following: Teoloyucan

Problem: Madonna's music has been the subject of much analysis and scrutiny. Robert M. Grant, author of Contemporary Strategy Analysis (2005), commented that what has brought Madonna success is "certainly not outstanding natural talent. As a vocalist, musician, dancer, songwriter, or actress, Madonna's talents seem modest." He asserts Madonna's success is in relying on the talents of others, and that her personal relationships have served as cornerstones to the numerous reinventions in the longevity of her career. Madonna's approach was far from the music industry wisdom of "Find a winning formula and stick to it." Her musical career has been a continuous experimentation with new musical ideas and new images and a constant quest for new heights of fame and acclaim. Grant concluded that "having established herself as the queen of popular music, Madonna did not stop there, but continued re-inventing." Musicologist Susan McClary wrote that "Madonna's art itself repeatedly deconstructs the traditional notion of the unified subject with finite ego boundaries. Her pieces explore various ways of constituting identities that refuse stability, that remain fluid, that resist definition."
Whose music had been the subject of a lot of scrutiny?
The answer is the following: Madonna's

Problem: Muslims believe the Quran was verbally revealed by God to Muhammad through the angel Gabriel (Jibril), gradually over a period of approximately 23 years, beginning on 22 December 609 CE, when Muhammad was 40, and concluding in 632, the year of his death. Muslims regard the Quran as the most important miracle of Muhammad, a proof of his prophethood, and the culmination of a series of divine messages that started with the messages revealed to Adam and ended with Muhammad. The word "Quran" occurs some 70 times in the text of the Quran, although different names and words are also said to be references to the Quran.
What is the Arabic variant of Gabriel?
The answer is the following:
Jibril