The correct option is D Cytoplasm
Sequence of chemical reactions catalyzed by cellular enzymes occurring in the cytoplasm of cells that breaks down glucose, that releases energy stored as ATP is called glycolysis.
One molecule of glucose makes two molecules of pyruvate and two molecules of ATP. The pyruvate either enters into the tricarboxylic acid cycle (mitochondrial matrix) in presence of adequate oxygen or is fermented into lactic acid or ethanol. Thus, glycolysis produces both ATP for cellular energy requirements and building blocks for synthesis of other cellular products.This process occurs in all organisms, and is responsible for converting glucose to pyruvate and generating ATP in the process. Glycolysis does not require oxygen to function.