<u>Answer:</u> Erosion
<em>The process in which there is a wearing down on the surface on the earth which goes through the erosion is called gradation.</em>
<u>Explanation:</u>
There is a certain force which is the cause for the <em>formation of earth’s surface and that force is called as endogenic forces. </em>
There may come up a question about how the <em>surface of the earth</em> is not even, the reason is due to exogenic process failing to even out <em>the variation of the land.</em>
Correct answer: D
A pollen is where male gametes are produced and so the number of chromosomes, as we are talking about gametes, is n. This means that the grain of pollen will only have a copy of each gene, and therefore only one allele for each gene - one S, and one T or t. So, the possible combinations are ST and St.
