Which of the following is a characteristic of malignant neoplasms?

Malignant neoplasms are characterized by their invasive nature and ability to metastasize, which distinguishes them from benign tumors. These tumors exhibit uncontrolled growth, often infiltrating surrounding tissues and organs, leading to the destruction of adjacent structures. This aggressive behavior is a hallmark of malignancy, making it a critical characteristic for identification and diagnosis.

Metastasis refers to the ability of cancer cells to break away from the primary tumor, travel through the bloodstream or lymphatic system, and establish new tumors in distant organs. This capability significantly complicates treatment, as it indicates a more advanced disease state and poses a greater risk to the patient's health.

The other characteristics listed do not align with the defining traits of malignant neoplasms. For instance, localized tumors that are not invasive are typical of benign neoplasms, while those that promote healing are not a characteristic of malignancy. Similarly, neoplasms that are non-invasive and easily removed through surgical procedures also classify as benign, contrasting sharply with the nature of malignant tumors.