D. Made of ash and pieces of rock rich in silica.
Should be your answer!
The longest phase of mitosis is prophase. Because the nuclear membrane disappears, Nucleolus disintegrates, and the DNA condensed to form chromosomes (each chromosome is composed of sister chromatids attached around centromere.)
In multi-celullar organisms , the cell cycle produces groups of cells that perform the same function. These groups of cells form what it is called a tissue. A tissue is made up of cells that all are specialised to perform the same function. A bunch of tissues form an organ. Organs are more complex in structure and functions.
lots of different organs together form an organ system.
I believe the answer is linear :)