In hexaploid wheat, what are the haploid $(n)$ and basic $(x)$ chromosome numbers?

Match the following and choose the correct option:

Column-$I$	Column-$II$
$(p)$ Mendel	$(i)$ Chromosomal theory of Inheritance
$(q)$ Morgan	$(ii)$ Recombination map
$(r)$ Alfred Sturtevant	$(iii)$ Linkage
$(s)$ Sutton	$(iv)$ Law of Segregation

In humans, albinism is controlled by a recessive gene '$a$'. If both parents are known to be carriers $(Aa)$ for albinism, what is the probability of having $1$ normal and $3$ albino children in a family of $4$ (in $/256$)?

In which one of the following combinations $(a-d)$ of the number of chromosomes is the present day hexaploid wheat correctly represented?

Combination

Monosomic,Haploid,Nullisomic,Trisomic

$Statement A$: For a particular character in an individual,each gamete gets only one allele.
$Statement B$: Chromatids of a chromosome split (separate) and move towards opposite poles during anaphase of mitosis.

Assertion $A$: Gene is the unit of inheritance.
Reason $R$: The properties of tissues are due to the constituents of their cells.
Which option is correct for Assertion $A$ and Reason $R$?