Compare the knowledge of persons $X, Y, Z, A, B$ and $C$ in relation to each other.
$X$ knows more than $A$.
$Y$ knows as much as $B$.
$Z$ knows less than $C$.
$A$ knows more than $Y$.
The best knowledgeable person amongst all is:

Consider the following:
$1.$ Saxena,David,Jain,and Kumar were District Collectors at places $P, Q, R,$ and $S$ respectively in $1970$.
$2.$ In $1972$,they were transferred; Saxena and Jain interchanged places. Kumar and David also interchanged places.
$3.$ One year later in $1973$,they were again transferred such that David and Jain interchanged places,and Saxena and Kumar were also interchanged.
What should be the next round of transfers so that all the four persons could have been posted at all the four places?

There are four friends $A, B, C, D$. One of them is a cricketer and studies Chemistry and Biology. $A$ and $B$ play football. Both football players study Maths. $D$ is a boxer. One football player also studies Physics. The boxer studies Maths and Accounts. All the friends study two subjects each and play one game each.
Who studies Physics?

$A, B, C, D, E, F,$ and $G$ are members of a family consisting of $4$ adults and $3$ children,two of whom,$F$ and $G$,are girls. $A$ and $D$ are brothers and $A$ is a doctor. $E$ is an engineer married to one of the brothers and has two children. $B$ is married to $D$ and $G$ is their child. Who is $C$?

There are six persons $A, B, C, D, E$ and $F$ in a school. Each of the teachers teaches two subjects,one compulsory subject and the other optional subject. $D$'s optional subject was History while three others have it as a compulsory subject. $E$ and $F$ have Physics as one of their subjects. $F$'s compulsory subject is Mathematics,which is an optional subject of both $C$ and $E$. History and English are $A$'s subjects,but in terms of compulsory and optional subjects,they are the reverse of $D$'s. Chemistry is an optional subject of only one of them. The only female teacher in the school has English as her compulsory subject. Who is the female member in the group?

Five friends $A, B, C, D$ and $E$ are sitting on a bench.
$1.$ $A$ is sitting next to $B$.
$2.$ $C$ is sitting next to $D$.
$3.$ $D$ is not sitting with $E$.
$4.$ $E$ is on the left end of the bench.
$5.$ $C$ is on the second position from the right.
$6.$ $A$ is on the right side of $B$ and to the right side of $E$.
$7.$ $A$ and $C$ are sitting together.
Who is sitting in the centre?