Use the Following Description to Answer the Question Below

question 39

Multiple Choice

Use the following description to answer the question below.
On the volcanic, equatorial West African island of Sao Tomé, two species of fruit fly exist. Drosophila yakuba inhabits the island's lowlands, and is also found on the African mainland, located about 200 miles away. At higher elevations, and only on Sao Tomé, is found the very closely related Drosophila santomea. The two species can hybridize, though male hybrids are sterile. A hybrid zone exists at middle elevations, but hybrids there are greatly outnumbered by D. santomea. Studies of the two species' nuclear genomes reveal that D. yakuba on the island is more closely related to mainland D. yakuba than to D. santomea (2n = 4 in both species) . Sao Tomé rose from the Atlantic Ocean about 14 million years ago.
If the low number of hybrid flies in the hybrid zone, relative to the number of D. santomea flies there, is due to the fact that hybrids are poorly adapted to conditions in the hybrid zone, and if fewer hybrid flies are produced with the passage of time, these conditions will most likely lead to ________.

• A) fusion
• B) reinforcement
• C) stability
• D) further speciation events

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Definitions:

Pounds

A unit of weight commonly used in the United States and the British imperial system, equivalent to 0.453592 kilograms.

Milliliters

A metric unit of volume equal to one-thousandth of a liter, used often to measure liquids in scientific and everyday contexts.

Ounces

A unit of weight commonly used in the United States, where one pound is equal to 16 ounces.

Soft Drink

A soft drink is a non-alcoholic beverage, usually carbonated, flavored with various sweeteners and other ingredients.