Marriages between close relatives should be avoided because they have a higher incidence of:

If a color-blind woman marries a man with normal vision,their sons will be .....

$A$ color-blind woman marries a man with normal vision. In their offspring,.........

What is the full form of $PKU$?

Phenylketonuria is a genetic disorder of

Autosomal dominant disorder $- P$
Autosomal recessive disorder $- Q$
$X$-linked recessive disorder $- R$
$I -$ Haemophilia,$II -$ Sickle cell anaemia,$III -$ Phenylketonuria,
$IV -$ Thalassaemia,$V -$ Colour blindness,$VI -$ Myotonic dystrophy
Select the correct option for $P, Q$ and $R$.
$\quad\quad P \quad\quad Q \quad\quad R$