Questions

A greenhouse gas (GHG) is any gas in the atmosphere that absorbs and emits radiation in the thermal infrared range.

The increase in average global temperatures that results from an enhanced greenhouse effect.

Effects of increased greenhouse gas emissions:

Increases in the different greenhouse gases have other effects apart from global warming including ocean acidification, smog pollution, ozone depletion as well as changes to plant growth and nutrition levels.

Para-amino salicyclic acid (PAS) is used in the treatment of Tuberculosis.

Answer: U

Explanation:   Starting on the left, and moving along the line to the right, letters follow the alphabetic sequence, in steps of 1,2,3 and then 4, before repeating the sequence.

Designers stay current by reading magazines, browsing the internet, attending fashion shows, and studying technical manuals. They study the history of fashion to better understand its development and current tendencies.

Small means a little in size or quantity.

Here in the given options, Tiny means same as small.

Hence, Small most nearly means as Tiny.

A restrictive clause is one that limits the meaning of the word it describes.

For example :: 

The girl who lives next door is beautiful.

This restrictive clause limits "the girl" to say it's specifically the one next door.