Concept:Cell growth is the increase in the size or mass of a single cell, not cell division.
Explanation:When a cell grows, it synthesises new cytoplasm and produces more organelles such as mitochondria and ribosomes.
External factors may affect growth, but it is not solely controlled by them, so option A is false.
Growth is not continuous throughout the cell's life because it pauses during cell division, so option B is false.
Cell division increases the number of cells, while cell growth increases the size of an existing cell, so option D is false.
Thus, the correct statement is option C.
Answer:C. Cell growth involves an increase in the number of organelles within a cell.