| While circulating heated sulfuric acid through a feed water heater of a flash evaporator for the purposes of scale removal, what would be the indication of the continued presence of scale? |
| A) No change in color (remaining at red with a pH of 2.0) and continued venting of carbon dioxide gas. |
| B) No change in color (remaining at red with a pH of 2.0) and no more venting of carbon dioxide gas. |
| C) Change in color (turning to orange with a pH of 4.0) and continued venting of carbon dioxide gas. |
| D) Change in color (turning to orange with a pH of 4.0) and no more venting of carbon dioxide gas. |
