Answer:
B) Krebs cycle (citric acid cycle)
Explanation:
Glycolysis breaks glucose into two pyruvate molecules. Pyruvate is decarboxylated into acetyl CoA and the reaction occurs in the matrix of mitochondria. In the mitochondrial matrix, acetyl CoA enters Kreb's cycle and is broken down into CO2 and H2O. For one molecule of acetyl CoA, two molecules of CO2 are released as a by-product. Therefore, out of three carbon atoms of pyruvate, two are released as CO2 during Kreb's cycle.
Answer: C
The substance that must come through the cell membrane for the cell to live is nutrients. Cells would die if they did not get nutrients. Nutrients are what keeps the cell running.
Most likely A from my point of view