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Reading Passage
Crude mineral oil comes out of the earth as a thick brown or black liquid with a strong smell. It is a complex mixture of many different substances, each with its own individual qualities. Most of them are combinations of hydrogen and carbon in varying proportions. Such hydrocarbons are also found in other forms such as bitumen, asphalt and natural gas. Mineral oil originates from the carcasses of tiny animals and from plants that live in the sea. Over millions of years, these dead creatures form large deposits under the sea-bed; and ocean currents cover them with a blanket of sand and silt. As this mineral hardens, it becomes sedimentary rock and effectively shuts out the oxygen, so preventing the complete decomposition of the marine deposit's underneath. The layers of sedimentary rock become thicker and heavier. Their pressure produces heat, which transforms the tiny carcasses into crude oil in a process that is still going on today.

Sedimentary rock leads to the formation of oil deposits because

20132Mprelimsupscyear-2013p2csatreading-comprehension
A.There are no saline conditions below it
B.It allows some dissolved oxygen to enter the dead organic matter below it
C.Weight of overlying sediment layers causes the production of heatCorrect
D.It contains the substances that catalyse the chemical reactions required to change dead organisms into oil
Explanation & Solution

Correct Option: (C) Weight of overlying sediment layers causes the production of heat

The passage states that 'The layers of sedimentary rock become thicker and heavier. Their pressure produces heat, which transforms the tiny carcasses into crude oil'

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पठित परिच्छेद
Crude mineral oil comes out of the earth as a thick brown or black liquid with a strong smell. It is a complex mixture of many different substances, each with its own individual qualities. Most of them are combinations of hydrogen and carbon in varying proportions. Such hydrocarbons are also found in other forms such as bitumen, asphalt and natural gas. Mineral oil originates from the carcasses of tiny animals and from plants that live in the sea. Over millions of years, these dead creatures form large deposits under the sea-bed; and ocean currents cover them with a blanket of sand and silt. As this mineral hardens, it becomes sedimentary rock and effectively shuts out the oxygen, so preventing the complete decomposition of the marine deposit's underneath. The layers of sedimentary rock become thicker and heavier. Their pressure produces heat, which transforms the tiny carcasses into crude oil in a process that is still going on today.

Sedimentary rock leads to the formation of oil deposits because

A.There are no saline conditions below it
B.It allows some dissolved oxygen to enter the dead organic matter below it
C.Weight of overlying sediment layers causes the production of heatसही
D.It contains the substances that catalyse the chemical reactions required to change dead organisms into oil

सही उत्तर: (C) Weight of overlying sediment layers causes the production of heat

The passage states that 'The layers of sedimentary rock become thicker and heavier. Their pressure produces heat, which transforms the tiny carcasses into crude oil'

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