<h2>
Reproductive Method </h2>
Explanation:
<em>The rank in order from the most specific which is following .</em>
<em>(1) Reproductive isolating mechanism</em>
<em>(2) Sperm-egg incompatibility in sea urchins</em>
<em>(3) Gametic isolation </em>
<em>(4)Prezygotic isolating mechanism</em>
<em>(1) Reproductive isolating mechanism-</em> The components of regenerative confinement are an assortment of transformative instruments, practices and <em>physiological procedures basic for speciation.</em> They keep individuals from various species from delivering posterity, or guarantee that any posterity are sterile.
(<em>2) Sperm-egg contradiction in ocean urchins-</em> Bindin is a gamete acknowledgment protein known to control species-explicit <em>sperm-egg grip</em> and layer combination in ocean urchins.
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(3)Gametic isolation - Prezygotic hindrances </em>keep preparation from occurring. Gametic disengagement is a sort of prezygotic hindrance where the<em> gametes (egg and sperm) </em>come into contact, yet no preparation happens. Gametes might be not able to remember each other in various species
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(4) Prezygotic isolating mechanism- </em>while postzygotic segregation forestalls the arrangement of rich posterity. Prezygotic systems incorporate environment segregation, mating seasons, "mechanical" disconnection, gamete detachment and conduct seclusion.
I believe it’s A in the question
The answer is,Different animals with similar structures:)
The biggest difference between the equinox and the solstice is that a solstice is the point during the Earth's orbit around the sun at which the sun is at the greatest distance from the equator, while during an equinox, it's at the closest distance from the equator. Because of this, one solstice is an extremely long day, and the other is an extremely short day. Comparatively, during an equinox, the days and nights are equal lengths.