These huge waves wreak terrific damage when they crash on the shores

Question

These huge waves wreak terrific damage when they crash on the shores of distant lands or continents. Under a perfectly sunny sky and from an apparently calm sea, a wall of water may break twenty or thirty feet high over beaches and waterfronts, crushing houses and drowning unsuspecting residents and bathers in its path.

How are these waves formed? When a submarine earthquake occurs, it is likely to set up a tremendous amount of shock, disturbing the quiet waters of the deep ocean. This disturbance travels to the surface and forms a huge swell in the ocean many miles across. It rolls outward in all directions, and the water lowers in the center as another swell looms up. Thus, a series of concentric swells are formed similar to those made when a coin or small pebble is dropped into a basin of water. The big difference is in the size. Each of the concentric rings of basin water traveling out toward the edge is only about an inch across and less than a quarter of an inch high. The swells in the ocean are sometimes nearly a mile wide and rise to several multiples of ten feet in height.

Many of us have heard about these waves, often referred to by their Japanese name of “tsunami.” For ages they have been dreaded in the Pacific, as no shore has been free from them. An underwater earthquake in the Aleutian Islands could start a swell that would break along the shores and cause severe damage in the southern part of Chile in South America. These waves travel hundreds of miles an hour, and one can understand how they would crash as violent breakers when caused to drag in the shallow waters of a coast.

Nothing was done about tsunamis until after World War II. In 1947 a particularly bad submarine earthquake took place south of the Aleutian Islands. A few hours later, people bathing in the sun along the quiet shores of Hawaii were dashed to death and shore-line property became a mass of shambles because a series of monstrous, breaking swells crashed along the shore and drove far inland. Hundreds of lives were lost in this catastrophe, and millions upon millions of dollars’ worth of damage was done.    1 
 1. One surprising aspect of the waves discussed in the passage is the fact that they

(A) are formed in concentric patterns
(B) often strike during clear weather
(C) arise under conditions of cold temperature
(D) are produced by deep swells
(E) may be forecast scientifically

2 
 2. The waves discussed in the passage often strike

(A) along the coasts of the Aleutian Islands
(B) in regions outside the area monitored by the Coast and Geodetic Survey
(C) at great distances from their place of origin
(D) at the same time as the occurrence of earthquakes
(E) in areas outside the Pacific region

3 
 3. It is believed that the waves are caused by

(A) seismic changes
(B) concentric time belts
(C) atmospheric conditions
(D) underwater earthquakes
(E) storms

4 
 4. A possible title for the passage could be

(A) How Submarine Waves Are Formed
(B) How to Locate Submarine Earthquakes
(C) Underwater Earthquakes
(D) “Tsunami” Waves
(E) How to Prevent Submarine Earthquakes

Sajjad1994 · Answer

Official Explanation

1. One surprising aspect of the waves discussed in the passage is the fact that they

Explanation

See paragraph 1: “Under a perfectly sunny sky and from an apparently calm sea . . .”  None of the other answer choices is particularly surprising.

Answer: B

Sajjad1994 · Answer

Official Explanation

4. A possible title for the passage could be

Explanation

While  (B)  and  (E)  suggest desirable actions, they are not mentioned in the passage.  (C)  and  (D)  provide far less information than alternative  (A) .

Answer: A

gullyboy09 · Answer

Hi  Sajjad1994 ,  Bunuel , for Q4, option A, it is very narrow, been discussed in only second paragraph, whereas whole passage talks about formation, a bit historical background etc, so D would be a better choice, the text describes the nature of these waves, their specific name (tsunami), their formation (earthquakes), their movement across the ocean, and the historical devastation they have caused, D is more comprehensive, talk about "waves".

guddo · Answer

4. A possible title for the passage could be
 
The passage opens with the destructive effects of these waves, but its main job is to explain  how they are produced . It says a submarine earthquake disturbs deep ocean water, creates huge swells, and sends them outward until they become violent breakers near shore. The name “tsunami,” the example from Hawaii, and the background details are all supporting material around that central explanation.

(A) How Submarine Waves Are Formed

This is the best answer. The core of the passage is the process by which these waves originate and develop after an underwater earthquake.

(B) How to Locate Submarine Earthquakes

This is wrong. The passage never discusses any method for locating earthquakes.

(C) Underwater Earthquakes

This is too narrow and also shifts the focus. Earthquakes are only the cause of the waves; the passage is mainly about the waves themselves and how they form.

(D) “Tsunami” Waves

This is tempting because the passage is about tsunamis in general. But it is less precise than A. The passage is not just describing tsunamis broadly; it mainly explains how they are formed and why they become destructive.

(E) How to Prevent Submarine Earthquakes

This is unsupported. Nothing in the passage is about prevention.

Answer: (A)

These huge waves wreak terrific damage when they crash on the shores

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Reading Comprehension (RC) Questions

These huge waves wreak terrific damage when they crash on the shores

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards