$CNG$ is considered a more efficient fuel. Which of the following statements is incorrect regarding it?

Some toxic substances present in industrial waste water can undergo $.........$ in the aquatic food chain.

What is Noise? State the effects of it and mention the measures to control it.

Select the correct option regarding algal bloom.
$I-$ Excessive growth of planktonic algae occurs due to the presence of high amounts of nutrients in water bodies.
$II-$ Algal bloom imparts a distinct color to the water bodies.
$III-$ Algal bloom causes deterioration of water quality and fish mortality.
$IV-$ All bloom-forming algae are highly toxic to humans and animals.

Particulate matter with a diameter of $2.5$ micrometres or less and a sound level of $150$ $dB$ or more causes the greatest harm to human health.

Which of the following pollutants is released in the largest quantity from the exhaust emissions of petrol/diesel automobiles?