Containers used in the volumetric conversion to weight of squid must be made from what material?

The correct choice emphasizes that containers must be made from non-absorbent material when converting the volume of squid to weight. This requirement ensures that the container does not absorb any liquid or moisture from the squid itself, which could lead to inaccuracies in measurement. Non-absorbent materials maintain the integrity of the sample by preventing any loss of liquid that would otherwise result in an underestimation of the actual weight of the squid. Using a container that does absorb moisture would compromise the reliability of the volumetric measurement, as the weight could vary based on the amount of liquid absorbed during the process.

In contrast, while other options describe certain characteristics of containers, they do not address this critical aspect of maintaining accurate weights. For instance, the shape or openings of the container might contribute to other factors like airflow or ease of measurement, but they do not directly affect the accuracy of the weight conversion as the use of non-absorbent materials does.