Even after you eat a sweet dessert, the level of glucose in your blood stays relatively constant. this is an example of the maintenance of relatively constant internal conditions despite fluctuations in the external environment.. .

This is an example of homeostasis, the maintenance of relatively constant internal conditions despite fluctuations in the external environment

Regulation of glucose levels in the blood is just one of many examples of homeostasis in the body.

Glucose blood levels are regulated by the balance of insulin and glucagon.

Insulin is hormone secreted by the pancreas in response to increased blood glucose following a meal such as sweet desert.

Glucagon, on the other hand is a hormone with opposite function ( its release from the pancreas occurs in response to decreased glucose level, so glucagon promotes glucose production).

c. earths continental crust is thicker than its lithosphere.

because, the lithosphere is the outermost layer of the earth/ 100 km thick and is defined by its machanical properties.the lithosphere contains oceanic and continental crust that varies in age and thickness across locations and geologic time. the lithosphere is the coolest layer of the earth in terms of temperature. the term lithosphere should not be confused with the use of "geosphere" which is used to indicate all of earth systems, including the atmosphere, hydrosphere   and biosphere. the surface of the earth can be divided into the continental crust and the oceanic crust.   the continental crust is made mostly of granite while the oceanic crust is made of basalt. the average thickness of the continental crust is 25 miles and the average thickness of the oceanic crust is 5 miles.   three types of rock, igneous, sedimentary, and metamorphic, make up the surface of the earth. that's why 3 option is preferable.

b. to discover aspects of the natural world.

hopefully i .