The scientific term for the formation of a new species is speciation. So, the correct answer would be letter d. :)
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The correct answer for this question is:
A farmer planted legumes and cabbage in the same field that is devoid of fertilizers. The yield from this field is better than the cabbage planted inanother field without legumes. The reason for this is because (A) <span>nitrogen-fixing present in the roots of legumes aid enrichment of nitrogen in the soil.</span>
Answer:
The function of the pleura is to allow optimal expansion and contraction of the lungs during breathing. The pleural fluid acts as a lubricant, allowing the parietal and visceral pleura to glide over each other friction free. This fluid is produced by the pleural layers themselves.