Which of the Following Is True of the Magma Formed

question 87

Multiple Choice

Which of the following is true of the magma formed from subducted ocean floor material that is eventually incorporated into continental crust?

• A)the composition of the magma changes from a high silica content to a lower silica content by the incorporation of sediments and other materials when it melts.
• B)the magma that forms in this way tends to produce more violent volcanic eruptions than magma derived directly from the aesthenosphere.
• C)batholiths may create magma as they move downward into the subduction zone.
• D)it has a low viscosity and rises easily to spread over the surface of the continental crust.
• E)because this magma is exactly like the magma at sea-floor spreading centres,it creates new oceanic crust at the surface.

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Definitions:

Oligopolistic Industry

An industry characterized by a small number of firms controlling the majority of the market share, leading to limited competition.

International Cartel

An agreement between companies, often from different countries, to control prices, limit production, or divide markets for goods or services internationally, thereby reducing competition.

Noncollusive Oligopoly

A market structure where a few companies dominate but do not illegally agree to control prices or market share.

Monopolistically Competitive

A market structure where many firms sell products that are similar but not identical, allowing for competition based on quality, price, and marketing.