In the following question, the sentence given with blank to be filled in with an appropriate word. Select the correct alternative out of the four and indicate it by selecting the appropriate option.
A sentence has been given in Active/Passive Voice. Out of the four given alternatives, select the one which best expresses the same sentence in Passive/Active Voice.
When iron is exposed to moist air, a reddish brown coating of hydrated Iron (III) Oxide (Fe2O3) is deposited on its surface. This reddish brown coating is called