What is the product formed when $RCH = CH_2$ is treated with $B_2H_6$ followed by oxidation with alkaline $H_2O_2$?

Identify $X, Y$ and $Z$ in the following reactions:

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R.$
Assertion $A :$ Treatment of bromine water with propene yields $1-$bromopropan$-2-$ol.
Reason $R:$ Attack of water on bromonium ion follows Markovnikov rule and results in $1-$bromopropan$-2-$ol.
In the light of the above statements,choose the most appropriate answer from the options given below:

The number of sigma $(\sigma)$ bonds in but-$1$-ene is.......

The reaction $CH_2=CH_2 + H_2 \xrightarrow{Ni, 300^{\circ}C} CH_3-CH_3$ is known as:

Assertion $(A)$: Reaction of $but-1-ene$ with $HBr$ gives $1-bromobutane$ as the major product.
Reason $(R)$: Addition of $HBr$ to unsymmetrical alkenes proceeds according to Markovnikov's rule.
The correct answer is