In geology, a graded<span> bed is one </span>characterized by<span> a systematic change in grain or clast size from one side of the bed to the other. Most commonly this takes the form of normal grading, with coarser sediments at the base, which grade upward into progressively finer ones.</span>
Answer: Option (A) and (C)
Explanation: In case of slow sea floor spreading, the magma within the crust doesn't get proper way to exert the force upward because of its slower rate of spreading. Due to this, rifting occurs along the mid oceanic ridge.
Due to continuous rifting, it forms a valley known as the rift valley. This rift valley lacks in ridge and is comparatively smooth compared to a fast spreading sea floor, in which the topography appears to be rough and ridges are formed.
Thus, the statements that are true are option (A) and (C).
A likely natural feature in an extremely densely populated area would be a well watered, fertile plain. An example is the Northern plain of India also called the Indo - Gangetic plain. It s on one of the world's most densely populated area per square kilometer. This plain is formed from the flood plains of three great river systems - the Indus, the Ganga and the Brahmaputra. The soil cover in the plain is rich and fertile and water is found in plenty. These factors combined with a favorable climate makes it one of the most intensely farmed and populated areas in the globe.
