I think that the answer would be a or d.
i dont know.
Hope this helps
Answer:
"it was once part of the organisms from which the fossil fuels formed"
Inferiority, as he would feel inferior to his peers.
By the late 1830s, botanist Matthias Schleiden and zoologist Theodor Schwann were studying tissues and proposed the unified cell theory. The unified cell theory states that: all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells.