True or False: Fumigants can only kill pests if they remain in their liquid or solid form.

Fumigants are effective in controlling pests primarily due to their gaseous state. When fumigants are applied, they typically vaporize and permeate the area being treated. This ability to transition from liquid or solid to gas allows the fumigant to penetrate materials and reach pests that may be hiding in crevices or within stored goods.

Being in a gaseous form enables the fumigant to diffuse throughout the treatment area, ensuring that pests can be accessed regardless of their physical location. Therefore, the claim that fumigants can only kill pests if they remain in liquid or solid form is inaccurate. Fumigants are designed to function as gases to effectively manage and eradicate various types of pests across different environments.

The other options imply specific conditions under which fumigants may operate, such as being only effective for certain types or depending on temperature, but these do not capture the fundamental characteristic of how fumigants work—namely, that it is their gaseous state that allows for broad-spectrum pest control.