Why are bullocks more docile than bulls?

Assertion $A$: Milk is a useful product used as a valuable food.
Reason $R$: It is the fresh natural secretion of the mammary glands of female mammals for the nourishment of their young ones.
Which option is correct for Assertion $A$ and Reason $R$?

Which of the following is a domesticated livestock of high mountains?

Match the following columns:

Column-$I$	Column-$II$
$P$. Inbreeding	$I$. Mating between male and female of two different related species
$Q$. Out-crossing	$II$. Mating of animals within the same breed that have no common ancestors on either side for $4-6$ generations
$R$. Cross-breeding	$III$. Mating of more closely related individuals within the same breed for $4-6$ generations
$S$. Interspecific hybridization	$IV$. Mating of superior male of one breed with superior female of another breed

Compared to a bull,a bullock is docile because of:

When breeding is between animals of the same breed for $4-6$ generations,it is called: