Digest and recycle the cell's used components by breaking down proteins, nucleic acids, lipids, and carbohydrates. a). vesicles . b). ribosomes . c). lysosomes . d). endoplasmic reticula

A lysosome is spherical membrane-bound organelle. In the lysosome, there are many hydrolytic enzymes which role is to break down different kind of molecules and components used by the cell. The pH inside of the lysosome is low (acidic: 4.5 - 5.0) which is optimal for enzymes. Also, there are substances involved in energy metabolism, cell signalling, etc.

the answer is lactic acid from anaerobic respiration. the acid in lactic acid is what creates sore and burning muscles. if you think about how acid burns that will give you a clue for questions like this.