This option is correct as  penicillin is a narrow spectrum antibiotic and effective against diseases caused by various cocci and some gram positive bacteria.

The substance which neutralises excess acid in the stomach and raises the pH to an appropriate level is called an antacid. Hence, this option is correct.

This option is correct as dettol and savlon are antiseptics. Antiseptics are chemicals that are used externally to prevent the growth of microbes or pathogens. Antibiotics are anti-bacterial drugs but antiseptics are active against bacteria as well as other microbes. Antiseptics are milder in comparison to the disinfectants and hence they can be applied on the skin. All antimicrobial chemicals are not antiseptics.

This option is correct as antibacterial drugs are antibiotics.

PVC is the third-most widely produced synthetic plastic polymer. It is a polymer of vinyl chloride (CH₂ = CH- Cl).

The gases released by burning these fibres are toxic and carcinogenic also.

 Plastic is a material consisting of any of synthetic or semi-synthetic organics that are malleable and can be molded into solid objects of diverse shapes. Plastics are typically organic polymers of high molecular mass, but they often contain other substances. They are usually synthetic, most commonly derived from petrochemicals, but many are partially natural.

Teflon is used for non-stick coating on cookware.

Coloured glass for goggles contains ferrous oxide.

Fertilisers and pesticides are not eco-friendly because of their deleterious effects on human health and the environment. They cause water pollution as well.

Flint glass has high refractive index and high dispersion. It contains mainly lead oxide.

Flint glass or optical glass is used for making high precision optical instruments.

Hard glass is prepared by fusing a mixture of potassium carbonate, calcium carbonate and silica.

This is the correct option as fertilisers, pesticides, petroleum oil and solid particles all are the causes of water pollution.

DDT is an organochlorine. Organic compounds that have been chlorinated, have very low biodegradation, get accumulated in environment and cause many problems. DDT comes under these. Hence, it is correct.