We want to write a code to create and store a sequence of numbers containing all possible digits from $1$ till $10$ such that adjacent numbers are separated by $2.$ Which of the following is a wrong solution.

$($a$)1.$N $<-$ seq$(1,10,$by $=2)$

$($b$)$N$\mathrm{.}1=$ c$(1,3,5,7,9)$

$($c$)$N$\mathrm{.}2=$ seq$(2,10,$ by $=10)$

$($d$)2\_$N $=$ c$(2,4,6,8,10)$