Answer:
The correct answer is None of these choices are correct.
Explanation:
Crossing over doesn't occur only between heterozygous genes, it also doesn't happen only in some chromosomes and it never reduces de variation, otherwise, the crossing over is one of the main causes of variation among species.
Solution:
The troposphere is the atmospheric layer closest to the planet and contains the largest percentage (around 80%) of the mass of the total atmosphere.
The troposphere is the lowest major atmospheric layer, extending from the Earth's surface up to the bottom of the stratosphere. The troposphere is where all of Earth's weather occurs. It contains approximately 80% of the total mass of the atmosphere.
The troposphere is characterized by decreasing temperature with height (at an average rate of 3.5 degrees F per thousand feet, or 6.5 degrees C per kilometer). In contrast, the stratosphere has either constant or slowly increasing temperature with height.
Thus the right answer is troposphere.
Half .
I think that’s right .
I believe it is seminal fluid.
Hope this helps :)
