Meiosis is associated with the

Meiosis is associated with the haploid number of chromosomes.

Meiosis is a specialized process of cell division in which a diploid cell (cell with two sets of chromosome) is divided by half to produce four haploid cells (cells with a single set of chromosomes), which develop to form gametes that are genetically to the parent cell that produced it. Meiosis takes place in all sexually reproducing unicellular and multicellular eukaryotes which includes animals, plants, and fungi. Sperm and eggs are the haploid cells made during meiosis in humans.  

oxygen +1 most likely

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.