Explanation

"Because" is a subordinating conjunction, commonly used in complex sentences to show cause or reason.

It connects an independent clause with a dependent clause, e.g., She stayed home because she was sick.

Explanation

: "Quickly" is an adverb, not a conjunction.

Explanation

"Nevertheless" is a conjunctive adverb used to connect and contrast two independent clauses.

Explanation

"Because" is the correct conjunction to show the reason for her fitness.

The sentence means she is fit due to the fact that she goes running every day.

Explanation

"However" shows contrast between going into the store and not finding anything to buy.

It connects two contrasting ideas in the sentence effectively.

Explanation

The words like for, and, nor, but, or, yet, and so are called: Coordinate Conjunctions.

"Or" is a coordinate conjunction, used to join two words, phrases, or clauses of equal importance.

Explanation

"So" is the conjunction in the sentence, as it connects two clauses: the reason (he was tired) and the result (he went to bed early).

It shows cause and effect between the two actions.

Explanation

Subordinate conjunctions join a dependent (subordinate) clause to an independent clause.

In this sentence, "because" introduces the reason (subordinate clause) for not attending the event.

Explanation

Whenever is a conjunction which means جب بھی

"Whenever" is the best choice because it indicates that Saira starts sneezing every time she opens the window to get fresh air.

It expresses a habitual or recurring action, making it the most appropriate conjunction for this sentence.

Explanation

Until is a conjunction.

Until means جب تک 

Until is correct because it indicates the time before spring arrives when preparation is needed.