Explanation
$${\textbf{Step -1: Put x=0 and change the sign as negative multiply by negative is positive}}$$ $${\textbf{and positive multiply by negative is negative }} $$
$$ x = 0 \Rightarrow - \times - \times - = - $$
$${\textbf{Step -2:Put x=1.5 and change the sign as positive multiply by negative is negative}}$$ $${\textbf{and negative multiply by negative is positive }}$$
$$x = 1.5 \Rightarrow + \times - \times - = + $$
$${\textbf{Step -3:Put x=2.5 and change the sign as positive multiply by positive is positive}}$$ $${\textbf{and positive multiply by negative is negative}}$$
$$x = 2.5 \Rightarrow + \times + \times - = - $$
$${\textbf{Step -4: Put x=4 and change the sign as positive multiply by positive is always positive }}$$
$$x = 4 \Rightarrow + \times + \times + = + $$
$${\text{x is positive between 1 and 2 and between 3 and infinity so }} x \in (1,2) \cup (3,\infty )$$
$$\textbf{Hence option B is correct}$$
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