Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 30 to 34.
As heart disease continues to be the number-one killer in the United States, researchers have become increasingly interested in identifying the potential risk factors that trigger heart attacks. High-fat diets and „life in the fast lane” have long been known to contribute to the high incidence of heart failure. But according to new studies, the list of risk factors may be significantly longer and quite surprising.
Heart failure, for example appears to have seasonal and temporal patterns. A higher percentage of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more susceptible to heart attacks in the first few hours after waking. Cardiologists first observed this morning phenomenon in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart-stimulating hormones, plus a reduction of blood flow to the heart, may all contribute to the higher incidence of heart attacks between the hours of 8:00 A.M and 10 A.M.
In other studies, both birthdays and bachelorhood have been implicated as risk factors. Statistics reveal that heart attack rates increase significantly for both females and males in the few days immediately preceding and following their birthdays. And unmarried men are more at risk for heart attacks than their married counterparts. Though stress is thought to be linked in some way to all of the aforementioned risk factors, intense research continues in the hope of further comprehending why and how heart failure is triggered.
Which of the following does the passage infer?
A. We now fully understand how risk factors trigger heart attacks
B. We recently began to study how risk factors trigger heart attacks
C. We have not identified many risk factors associated with heart attacks
D. We do not fully understand how risk factors trigger heart attacks
Cái nào dưới đây có thể được suy luận ra từ bài đọc?
A. Bây giờ chúng ta đã hoàn toàn hiểu được hết những nguy cơ này đã dẫn đến những cơn đau tim như thế nào.
B. Gần đây chúng ta mới bắt đầu nghiên cứu những nguy cơ đó đã dẫn đến cơn đau tim như thế nào.
C. Chúng ta vẫn chưa xác định được nhiều nguy cơ dẫn đến cơn đau tim.
D. Chúng ta vẫn chưa hiểu được hết những nguy cơ tiềm ẩn này dẫn đến các cơn đau tim như thế nào.
Thông tin: […] intense research continues in the hope of further comprehending why and how heart failure is triggered.
Tạm dịch: […] những nghiên cứu kĩ hơn sẽ tiếp tục với hi vọng có thể hiểu thêm tại sao và như thế nào dẫn đến các cơn suy tim.
Chọn D