Dilute hydrochloric acid reacts with $1\ \text{g}$ of limestone. Under which conditions is the rate of reaction fastest?
- A$2\ \text{mol dm}^{-3}$ hydrochloric acid and a single lump of limestone
- B$4\ \text{mol dm}^{-3}$ hydrochloric acid and a single lump of limestone
- C$4\ \text{mol dm}^{-3}$ hydrochloric acid and small pieces of limestone
- D$4\ \text{mol dm}^{-3}$ hydrochloric acid and powdered limestone