The upper crust of the earth consists mostly of silicates. The acidic rocks containing a larger proportion of silica do not include I.Dolerite II. Granite III.Basalt. IV.Quartz,

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Q: 66 (CDS-I/2004)
The upper crust of the earth consists mostly of silicates. The acidic rocks containing a larger proportion of silica do not include
I.Dolerite
II. Granite
III.Basalt.
IV.Quartz,

question_subject: 

Geography

question_exam: 

CDS-I

stats: 

0,14,45,17,14,11,17

keywords: 

{'acidic rocks': [0, 0, 1, 0], 'upper crust': [0, 0, 1, 0], 'silicates': [0, 0, 2, 0], 'silica': [1, 0, 5, 9], 'granite': [8, 0, 2, 5], 'earth': [0, 1, 1, 1], 'land iii': [0, 0, 1, 0]}

The upper crust of the earth is primarily composed of silicates, which are minerals made up of silicon and oxygen. These silicates make up a variety of rocks, including granite, basalt, and quartz.

Dolerite is a type of rock that is not included in the acidic rocks containing a larger proportion of silica. This means that option I, which includes dolerite, is incorrect.

Granite is an acidic rock that does contain a larger proportion of silica, so it is included in the group of rocks mentioned. Therefore, option II, which does not include granite, is also incorrect.

Basalt, on the other hand, is a type of rock that does contain a larger proportion of silica and is included in the acidic rocks. Therefore, option III, which does not include basalt, is also incorrect.

Quartz is a silicate mineral and is included in the acidic rocks containing a larger proportion of silica. Therefore, option IV, which does not include quartz, is also incorrect.

The correct answer is option 2, which states that dolerite and basalt are not included in the acidic rocks containing a larger proportion of silica.

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