we will select each options and then we verify it
(a)
since, this is greatest integer function
so, it's value will be equal to lesser integer value
so,
[tex] f(4.9)=4 [/tex]
so, this is FALSE
(b)
since, this is greatest integer function
so, it's value will be equal to lesser integer value
so,
[tex] f(-3.4)=-4 [/tex]
so, this is TRUE
(C)
This is FALSE
(D)
This is TRUE
(E)
Since, it does not satisfy horizontal line test
so, it is not one to one
so, this is FALSE