Final answer:
Methotrexate is an example of a cell-cycle nonspecific antineoplastic agent that disrupts cell division by inhibiting dihydrofolate reductase, an enzyme involved in DNA synthesis. It is used to treat various types of cancers.
Step-by-step explanation:
An example of a cell-cycle nonspecific antineoplastic agent is methotrexate. Methotrexate is a chemotherapy drug that disrupts cell division by inhibiting the enzyme dihydrofolate reductase, which is involved in the synthesis of DNA. This drug is effective against a variety of cancers, including breast, skin, placental, uterine, and lung cancers.