Answer: The correct answer would be copper, nickel, or zinc.
Explanation:
Heavy metals such as copper, zinc, nickel have antimicrobial properties due to which they are used in various places to prevent microbial growth. For example, copper sulfate is used in fish tanks and swimming pools to prevent algal growth. Metallic copper and/or copper linings in incubators also help in reducing microbial contamination.
Coating of nickel or zinc is also used for the same purpose.
Thus, the correct answer would be copper, nickel, or zinc.
