The correct answer is: B. Storm
A barometer is a device used to measure atmospheric pressure. The atmospheric pressure is the weight of the air above a given point on Earth. The higher the atmospheric pressure, the heavier the air and the more stable the weather. The lower the atmospheric pressure, the lighter the air and the more unstable the weather.
When the atmospheric pressure is low, it is an indication that a storm is approaching. This is because the low pressure allows the air to rise, which in turn causes clouds to form. The clouds can then produce rain, snow, or hail.
The other options are incorrect because they are not associated with low atmospheric pressure. Snow is associated with cold weather, which is typically associated with high atmospheric pressure. Intense heat is associated with high temperatures, which is also typically associated with high atmospheric pressure. Rainfall can occur in both high and low pressure systems, but it is more common in low pressure systems.