Which tool is used to transfer bacteria from one location to another?

The correct choice, the inoculating loop, is a specialized tool designed for transferring microorganisms, such as bacteria, from one medium to another. Its looped end allows for easy collection and transfer of bacterial cultures, making it especially effective for streaking on agar plates to isolate colonies or for inoculating broths and slants.

The inoculating loop is typically made of a metal wire that can be sterilized by flaming before and after use, ensuring that no contamination occurs during the transfer process. This ensures that only the desired bacterial strain is introduced into the new culture medium, which is vital for accurate microbiological work.

In contrast, the inoculating needle, while similar in that it can also transfer bacteria, is primarily used to stab into solid media rather than for spreading or streaking. Culture flasks are vessels used for growing microorganisms in bulk rather than transferring them, and petri dishes serve as containers for culturing bacteria but are not tools for transferring them.