Malignant cells are characterized by their ability to:

Malignant cells are best characterized by their ability to replicate indefinitely. This characteristic distinguishes them from normal cells, which typically have a finite number of divisions due to mechanisms like telomere shortening and the activation of apoptotic pathways. Malignant cells often gain the ability to bypass these limitations through various genetic alterations, allowing them to proliferate uncontrollably. This unrestricted growth is a hallmark of cancer, contributing to the formation of tumors and the potential for metastasis.

While the other options touch upon related concepts, they do not define malignant cells as effectively as the ability to replicate indefinitely. For example, apoptosis refers to programmed cell death, which malignant cells often evade, rather than actively undergo. Decaying rapidly may occur in certain contexts but is not a characteristic of malignant cells; rather, many thrive and expand. Regulating their own division is somewhat misleading, as malignant cells often lose the normal regulatory mechanisms that govern cell division, leading to their unchecked proliferation instead.