Which 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 leukemia, blood cell counts are decreased.
Choose the correct answer from the options given below:
Identify the part of the sentence that contains a grammatical error:
Each of the boys have submitted their assignment on time.
Rearrange the following parts to form a meaningful and grammatically correct sentence:
P. a healthy diet and regular exercise
Q. are important habits
R. that help maintain good physical and mental health
S. especially in today's busy world