Which of the following gases does not cause acid rain?

Given below are two statements:
Statement $I:$ In a scrubber,the exhaust from the thermal plant is passed through a spray of water or lime to remove gases like $SO_2$.
Statement $II:$ Particulate matter $(PM\,2.5)$ cannot be removed by a scrubber but can be removed by an electrostatic precipitator.
In the light of the above statements,choose the most appropriate answer from the options given below:

The following water samples are given with their $BOD$ values. Which sample has the lowest level of pollution?
Sample $w - 6 \ mg/L$,Sample $x - 6.5 \ mg/L$
Sample $y - 7 \ mg/L$,Sample $z - 10.3 \ mg/L$

$dB$ is a standard abbreviation used for the quantitative expression of

Two lakes,$A$ and $B$ are identical in all aspects except that lake $A$ has higher temperature. Which of the following is true?

Which of the following is $NOT$ an effect of noise pollution on humans?