Which of the following tweezers is used to isolate the lash that will have eyelash extensions placed on it?

Curved tweezers are specifically designed for isolating individual lashes because their shape allows for better access to the natural lash line. This design provides a more ergonomic grip and makes it easier to pivot and maneuver around the lashes. When applying eyelash extensions, precision is key, and curved tweezers help the technician to clearly isolate the lashes that will receive the extensions while minimizing the risk of touching or sticking to adjacent lashes.

While straight tweezers can also serve similar purposes, they are less common for the specific task of isolation due to their linear design, which may not allow for the same degree of precision in accessing and separating lashes. This makes curved tweezers the more effective choice for this particular task in the application process of eyelash extensions.