Why do sunspots appear darker than their surroundings? a. they are masked by dust and gas passing between earth and the sun. b. they are warmer than their surrounding environment. c. they are cooler than their surrounding environment. d. they have a strong gravitational pull, similar to black holes. e. they lie in the shadow cast by the moon and earth.

The correct answer is option C, that is, they are cooler than their surrounding environment.  

The regions of the solar surface where the Sun's magnetic field becomes 1000s times more concentrated are known as sunspots. The sunspots are actually many thousand degrees cooler in comparison to the surface of the Sun and comprise gases at temperatures of 3000 to 4000 K.  

The sunspots seem darker as they are darker in comparison to the surrounding surface, they are darker as they are cooler, and they are cooler due to the presence of intense magnetic fields.  

C.) They are cooler than their surrounding environment.

Explanation:

aquifers are bounded above and below by impermeable rock. the driving force of groundwater movement in confined aquifers is pressure, rather than gravity.

i do not get it   at all