Earth’s magnetic field results from movements in the
a. mantle.
b. outer core.
c. inner core.
d. crust.

The correct answer is option B  

According to the scientists the magnetic field on the earth is the result of the movement of nickel and iron within its liquid outer core. The flow of nickel and iron is caused due to the interaction between the earth's core and its mantle.

The earth's core and its mantle are neither even nor they are evenly distributed. So, electrical currents are generated by this flow and this results in the generation of the magnetic field.

stratosphere: as the altitude increases, the air temperature increases. the stratosphere has a layer of ozone, called the ozone layer. this layer absorbs most of the ultraviolet radiation from sunlight. this results in the stratosphere being warmer.

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation: