The populations living on a rough, steep mountain would have a higher rate of speciation than this living in a large, open grassland because the mountain would a. show less habitat fragmentation b. have less variety in the environment c. have a wider range of environments d. provide more natural resources

The correct answer is option C, that is, have a wider range of environments.  

It has been known that geographic isolation is a general way for the initiation of the process of speciation, like the rise of mountains, rivers changing course, migration of organisms, continental drift, due to this what was once a steady population gets differentiated into two or more kinds of smaller populations.  

A mountain range, due to distinctions in temperature and precipitation as a result of different altitudes, can lead to a higher rate of speciation. Due to these differences, a single mountain range can exhibit an enormous array of biodiversity and climate zones.

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