Last week, tickets to Adventure Theme Park were sold at half the usual

OA:

Question #1: The paradox here is that the cancer researchers are advocating against annual screenings because mammograms expose women to high radiation, even though mammograms as a whole can detect cancer effectively. Why would the cancer researches want to stop regular mammograms? Most likely if the mammograms themselves were believed to be causing the cancer they ultimately detect. If certain types of cancer have been found to be more prevalent since the introduction of mammography, this would help explain the researchers’ point of view. The correct answer is (E).
Question #2: The paradox here is that the fitness expert is advocating aerobic dancing, which could be considered high-impact, while criticizing running as too damaging for joints and ligaments. If the aerobic dancing is somehow benefiting joints and ligaments, even though it is high-impact, then it makes sense why the fitness expert would advocate aerobic dancing over running. The correct answer is (E).
Question #3: This paradox question is made slightly harder with the use of the word “EXCEPT.” This means that four of the five answer choices will explain why it could be true that more people would visit a theme park AFTER the promotional special week than DURING it. Look to eliminate those four systematically – the remaining choice will be correct! If a rival theme park increased their prices this week, this would indicate visitors would choose Adventure Theme Park over the rival theme park, but the paradox concerns the difference in the number of visitors at Adventure Theme Park from last week to this week. (C) does not pertain to last week at Adventure Theme Park. The correct answer is (C).

Source: GMAT Rockstar