Four test-tubes were arranged as shown in the table. In which test-tube would starch be broken down most quickly?
- A2 $\text{cm}^3$ starch suspension present; 1 $\text{cm}^3$ amylase present; 1 $\text{cm}^3$ boiled amylase absent; temperature $5^{\circ}\text{C}$
- B2 $\text{cm}^3$ starch suspension present; 1 $\text{cm}^3$ amylase present; 1 $\text{cm}^3$ boiled amylase absent; temperature $35^{\circ}\text{C}$
- C2 $\text{cm}^3$ starch suspension present; 1 $\text{cm}^3$ amylase absent; 1 $\text{cm}^3$ boiled amylase present; temperature $5^{\circ}\text{C}$
- D2 $\text{cm}^3$ starch suspension present; 1 $\text{cm}^3$ amylase absent; 1 $\text{cm}^3$ boiled amylase present; temperature $35^{\circ}\text{C}$