Reading Comprehension: Initial Reading

Which of the following sentences is/are necessarily NOT a part of the Initial Reading?       

        The question of the existence of liquid water on the surface of Mars has fascinated scientists for over three centuries, with new information repeatedly shedding new light on the subject. (1) Other than the significance of water in the geological research of Mars and its relevance to the study of the solar system as a whole, the existence of water also sparked the imagination of many in regards to the possibility of life on the Red Planet. Such speculations arose from the assumption that a planet's capability to develop and sustain life is highly dependent on the prevalence of liquid water on its surface.

        Originally, scientists speculated that Mars may have liquid water on it surface. The basis for this theory was changes in light and dark areas in the polar regions seen even by the most primitive telescopes, which were attributed to seas and continents. Furthermore, long dark lines visible across the surface were suggested by certain scientists to be irrigation channels, carrying liquid water. However, the dark features were consequently proven to be optical illusions, and after the first flyby of the Mariner 4 spacecraft in 1965, new data was discovered that discredited such assumptions.

        Information gathered by spacecrafts at the end of the 20th century and during the early years of the 21st century indicated that although liquid water was previously present on Mars' surface, it cannot exist there today due to Mars' low atmospheric pressure and distance from the sun. This information was collected by a group of orbiting spacecrafts, adjoined by telescopic observation of the planet from space and several landers and rovers which explored the planet's surface. These data brought scientists to believe Mars was previously largely covered in water, with geyser-like eruptions occurring even up to recent years.

        (2) Still, the debate over liquid water on Mars is far from being resolved and is continually fueled by new evidence. Currently, two rovers – Spirit and Opportunity – continue to explore the surface and broadcast information back to earth. In June 2007, an image from Mars of blue patches resembling water puddles was published by NASA; however, speculations were soon dismissed as the picture taken was of a sloped wall of a crater. (3) Despite such disappointments, some scientists still argue that as long as conclusive evidence regarding the nonexistence of liquid water on Mars is not found, the search must go on.

Good!

Sentence 2 is an integral part of the Initial Reading, which involves reading the first few sentences of the first paragraph and the first sentence of each of the remaining paragraphs.  

The question is which sentence is never a part of the Initial Reading. While the second sentence of the first paragraph is not always a part of the Initial Reading—if the first sentence of the first paragraph is enough to understand the main idea, there's no need to read the second sentence of the first paragraph—it more often than not is a part of the Initial Reading. 

Sentence 2 is an integral part of the Initial Reading, which involves reading the first few sentences of the first paragraph and the first sentence of each of the remaining paragraphs.

As for sentence 1, The question is which sentence is never a part of the Initial Reading. While the second sentence of the first paragraph is not always a part of the Initial Reading—if the first sentence of the first paragraph is enough to understand the main idea, there's no need to read the second sentence of the first paragraph—it more often than not is a part of the Initial Reading.

You're right about sentence 3. As for sentence 1, the question is which sentence is never a part of the Initial Reading. While the second sentence of the first paragraph is not always a part of the Initial Reading—if the first sentence of the first paragraph is enough to understand the main idea, there's no need to read the second sentence of the first paragraph—it more often than not is a part of the Initial Reading.

You're right about sentence 3. As for sentence 2, it is an integral part of the Initial Reading, which involves reading the first few sentences of the first paragraph and the first sentence of each of the remaining paragraphs. 

The question is which sentence is never a part of the Initial Reading. While the second sentence of the first paragraph is not always a part of the Initial Reading—if the first sentence of the first paragraph is enough to understand the main idea, there's no need to read the second sentence of the first paragraph—it more often than not is a part of the Initial Reading.

Sentence 2 is an integral part of the Initial Reading, which involves reading the first few sentences of the first paragraph and the first sentence of each of the remaining paragraphs.