Which of the following is a cancerous tumor?

$A$ benign tumour is one which:

Select the correct statements about cancer $:-$
$(A)$ Cancer cells show the property of contact inhibition.
$(B)$ Benign tumors normally remain confined to their original location and do not spread to other parts of the body.
$(C)$ Metastasis is the most feared property of benign tumours.
$(D)$ $X$-rays and gamma rays can lead to neoplastic transformation.
Choose the correct answer from the options given below :

Which of the following are methods of cancer treatment?

The diagnosis of cancer is based on which of the following?
$(1)$ Biopsy
$(2)$ Histopathological study of the tissue
$(3)$ Blood test
$(4)$ Bone marrow test

$A$: Cancer is contagious and cells can spread from one person to another.
$R$: Cancerous cells are highly dedifferentiated cells.