Dropsy means
Accumulation of the watery fluid in any part of the body
Accumulation of toxins in the body parts
Enlargement of kidney
Defective muscles of the eye
Vaccination protects a person from disease because it
Use of which causes destruction of chromosomes
$X$ - $CO$ is responsible for skin cancer
$Y$ - Strong magnetic field is used in $MRI$ to diagnose cancer
‘Black death' is related with
Which part of the body is known as ‘Police guard'