Answer: Wind-blown sand grains striking any solid object in their path can abrade the surface. Rocks are smoothed down, and the wind sorts sand into uniform deposits. The grains end up as level sheets of sand or are piled high in billowing sand dunes.
Explanation:
Ans. (B). XX, XY ,XX, XY ,XY, XX .
In pigs, the XY-sex determination system is found. According to this system, sex of the organisms can be determined by the presence of a pair of sex chromosomes.
Females have two X chromosomes (represented by XX), and known as homogametic sex, while males have one X and one Y chromosomes (represented by XY), and known as heterogametic sex.
Thus, the correct answer is option (B).
C. Dinosaur footprint as it is the only body part that is stated in the choices.
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D. Size of the oxygen atom compared to the hydrogen atom