Answer:
Option (A)
Explanation:
In the above-given question,
Option (B) is wrong with it's usage of the modifier "how'' in the sentence. If the modifier is used in one place (how heat from the inner core flows), it should also be used in the continuing clause (how the formation and periodic reversal).
Options (C) and (D) are wrong in using the word "are" for the whole sentence as there is no need to use this word. The verb form will depend on the subject, in this case, is "the discovery that earth's inner core" which is singular in nature. Thus, the verb form will be -is and not -are.
Option (E) is wrong for it's use of the comma. If the comma is used, then the whole sentence is not a full-fledged sentence but rather a dependent clause with no resolution.
The correct answer for the given passage is option (A).
Africa is the continent that has the most countries through which the Equator passes. In fact, 7 out of the 13 countries in the world through which the Equator passes are in Africa. From west to east they are in this order, Sao Tome and Principe, Gabon, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya, and Somalia. The Equator is an imaginary line invented by the humans for their own purposes. It basically is the line that separates the Earth into two equal parts horizontally, or rather into Northern Hemisphere and Southern Hemisphere. The Equator has latitude of 0 degrees, and it is the starting point from which the latitude is measured both north and south. This part of Africa is characterized with warm and wet climate, with the temperatures being constant throughout the whole year and have only few degrees of change, resulting in constant summer. The landscape is covered with dense tropical vegetation, and there's enormous amount of species that live in this area.
I think the correct answer would be the first option. Global belts of low and high air pressure are caused by horizontal air currents. Air current travels horizontally in the direction from low pressure to a high pressure zone. So, it is the horizontal movement of air that causes air pressure.
Child mortality rate is the rate of infants or young children who die in a certain area.