Which of the following is a sex-linked disease?

Polydactyly in humans is due to:

Identify the genotype of the first generation $(I)$ for an autosomal recessive disorder based on the provided pedigree chart.

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 $R$.
$\quad\quad P \quad\quad Q \quad\quad R$

Double lines in pedigree analysis show

More men suffer from colour blindness than women because