Complete the analogy
fact : fiction ::

unreal: delusion
disbelief: delusion
reality: delusion
fantasy: delusion

C. reality : delusion

Explanation:

In order to complete the analogy, we must first discover what the relationship between the two given words is.

- A fact is something that is absolutely true, backed by evidence

- A fiction is something that is made up, so it's not necessarily true

Ah, now we see: these two words are antonyms; in other words, they're opposites of each other, so we want to find a pair that is also made up of antonyms.

A: unreal : delusion

- unreal: this means something that isn't reality

- delusion: this is a false belief

These two words aren't really synonyms, but they're not antonyms, either, so eliminate.

B: disbelief : delusion

- disbelief: not believing something

- delusion: false belief

There isn't a really clear relationship between these two words, but we can definitely say that they're not antonyms, either, so eliminate.

C: reality : delusion

- reality: something that is true

- delusion: false belief

Ah, now we can see that these two are quite opposite, so this is the answer.

D: fantasy : delusion

- fantasy: a made-up, unreal world

- delusion: false belief

These aren't opposites either, so eliminate.

The answer is thus C.

the noun in this is person

the correct answer is option d. none of these. it is noted that options a, b, and c share the same content.

despite the valid answer provided at the last sentence of each of the options, a question/answer format shouldn't include humourous themed responses such as "you bet your thermal pj's we do." - unless of course, the answer is carried out in an informal environment. this could be replaced with a simple "yes" or "it is necessary".

the question should be re-phrased to a more appropiate syntaxis. instead of "do we need the greenhouse effect? ", it should be written as "is the greenhouse effect necessary? " in order to give it a general scope, instead of limiting the answer to the needs of "we" the humans.