Which attribute describes the ability of an organism to increase its mass by assimilating new materials?

The ability of an organism to increase its mass by assimilating new materials is defined as growth. Growth involves various processes where cells divide, differentiate, and increase in size, allowing the organism to develop from a smaller to a larger form. This process is crucial for life and is observed not only in multicellular organisms but also in unicellular ones as they take in nutrients, synthesize new cellular components, and expand.

Movement refers to the ability of an organism to change its position or location but does not directly relate to an increase in mass. Reproduction involves producing new individuals or offspring, which may lead to an increase in a population but does not pertain to the growth of a single organism. Adaptation concerns an organism's ability to adjust to its environment over time, enhancing survival and reproduction but does not specifically address the assimilation of materials to increase mass. Thus, growth is the most accurate descriptor of this attribute.