Final answer:
Isopropyl alcohol is the recommended cleaning agent for conductivity probes because it evaporates quickly, does not leave a residue, and effectively cleans the probes.
Step-by-step explanation:
To clean conductivity probes, which are sensitive instruments used to measure the electrical conductivity of a solution, it's important to use a cleaning agent that will not leave a residue and can effectively remove any contaminants. The options listed include various types of alcohols and other substances, each with different properties and uses.
For cleaning conductivity probes, isopropyl alcohol (d) is typically recommended because it evaporates quickly, does not leave a residue, and is effective at dissolving salts and organic materials that may have built up on the probe.
Isopropyl alcohol is a common cleaning agent that is used in rubbing alcohol and also in some glass cleaners due to its cleaning and disinfecting properties.