Final answer:
Carmustine (BCNU) and Streptozocin are both classified as alkylating agents, a category of chemotherapy drugs that add alkyl groups to DNA, leading to DNA damage and preventing its proper function.
Step-by-step explanation:
The question asks to classify Carmustine (BCNU) and Streptozocin among the given categories of chemotherapy drugs. Alkylating agents are a group of drugs that chemically modify DNA molecules, leading to a miscoding of DNA. These drugs, including Carmustine, work by adding alkyl groups to guanine bases in DNA, thus preventing proper DNA replication and function. On the other hand, Streptozocin is also an alkylating agent that has a similar mechanism of action, targeting cancer cells by causing DNA damage.
Antibiotics like anthracyclines intercalate with DNA and affect its functions. While Streptozocin may have antibiotic properties, it is primarily characterized as an alkylating agent within the context of cancer chemotherapy. Therefore, given the options presented, both Carmustine and Streptozocin are best classified as (a) alkylating agents.