ans is d.
f(x)=x+5
f(x)= 3x-100
f(x)= $x^{3}$+1
put any int values like .....-3,-2,-1,0,1,2,3.... you will get unique values for f(x).
=> they are one one.
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for f(x)= $x^{2}$ +1
we can get same values for 2 and -2, 3 and -3 , 4 and -4 and so on for f(x)
$\Rightarrow$ so it is not one one.
It is also not onto since we will never be able to get a f(x)=0 for any value of x. i.e. the range is not fully covered.