Interferons are useful in controlling which of the following?

Which of the following statements is correct?

Which of the following statements are correct?
$A.$ Computed tomography and magnetic resonance imaging detect cancers of internal organs.
$B.$ Chemotherapeutic drugs are used to kill non-cancerous cells.
$C.$ $\alpha$-interferon activates the cancer patients' immune system and helps in destroying the tumour.
$D.$ Chemotherapeutic drugs are biological response modifiers.
$E.$ In the case of leukaemia,blood cell counts are decreased.
Choose the correct answer from the options given below:

Explain the types of cancerous tumors.

Which of the following is used in the treatment of cancer?

Which technique is used to detect $HIV$ in $AIDS$ patients and to identify mutations in genes of suspected cancer patients?