Answer:
abyssal clay is not an example of biogenic sediments .
Explanation:
Any sediment containing more than 30% of organic matter in it , is called as biogenic sediment or biogenic ooze.
The two most common types of biogenic oozes are calcareous and sileceous.
abyssal clays are the fine grained sediment particles that are settled in the deep ocean basins.
abyssal clay mostly consists of land derived eroded particles and have less than 30% of organic matter in them ,
Hence , abyssal clay is not an example of biogenic sediment.
Fractional Crystallization
Geographers use the regional unit to map features of particular interest, and data can be compared between regions to help understand trends, identify patterns, or assist in explaining a particular phenomenon. Regions are traditionally defined by internal characteristics that provide a sense of place.
Concrete is not a crystal.
The answer should be C. In ocean trenches
