Final answer:
The correct statement regarding monsoonal circulations is that summer monsoons typically bring precipitation over continental surfaces, due to lower pressure over heated land drawing in moist oceanic air. So the correct option is C.
Step-by-step explanation:
The correct statement about monsoonal circulations is that summer monsoons tend to produce precipitation over continental surfaces. Monsoons are seasonal wind reversals accompanied by significant changes in precipitation patterns. They are driven by the differential heating of land and sea, not by a malfunction of the Hadley cell circulation. In the summer, the land heats up more than the ocean, leading to lower pressure over the land and higher pressure over the ocean. This pressure difference causes moist oceanic air to flow towards the land, rising and cooling to produce heavy rainfall. The strength of the monsoon is actually due to significant seasonal differences in surface heating, not a lack of it.
In South Asia, the summer monsoon is vital for agricultural production, as it brings the necessary precipitation to feed rivers, streams, and crops. Areas such as the Western Ghats and the northeastern part of Bangladesh significantly benefit from monsoon rains, receiving up to 18 feet of rainfall in some regions, while the Thar Desert remains arid with less than ten inches per year.