What is the first step to take if you break a glass beaker?

The first step to take if you break a glass beaker is to carefully sweep up the glass. This is the correct answer because it addresses the immediate safety concern by removing sharp glass fragments that could pose a hazard to anyone in the vicinity. Sweeping up the broken glass ensures that the area is safe, preventing injury and facilitating a safe continuation of work in the laboratory.

Leaving the area immediately could lead to other students or colleagues being unaware of the hazard left behind. Calling for help might be necessary later, but not as an immediate first response to ensure safety. Continuing with the experiment would clearly be inappropriate as it could lead to further accidents or injuries. Therefore, the most responsible and safety-conscious action is to first address the broken glass to protect yourself and others.