Select the most appropriate synonym of the given word. Necessary

Correct — A. Necessary means required, something that cannot be done without, and essential carries exactly that sense — indispensable, needed for the thing to work.

Substitution proves it: a necessary document and an essential document say the same thing.

The rest of the set only rhymes. Spatial, existential and potential share the -tial ending and nothing else, so option (a) is the one chosen on meaning rather than on sound.

Why the others are wrong

• (b)
  Spatial — Spatial means relating to space — spatial awareness, spatial data. It shares an ending with the keyed word and no part of its meaning.
• (c)
  Existential — Existential concerns existence itself, as in an existential question about why we are here. Necessary is about need, not about being.
• (d)
  Potential — Potential means possible but not yet actual, which pulls against necessary: potential says a thing may happen, necessary says it must.

A bare-word synonym item gives you no sentence, so the only defence is a family of meanings held in advance.

Necessary sits with essential, indispensable, requisite, vital and imperative. Against it stand optional, dispensable, needless and superfluous.

The distractor set here is built on sound, not sense — four words ending in -tial — which is a common way to make an easy word look hard. Say each option aloud with the meaning attached and the resemblance dissolves.

Key facts

• Necessary and essential both mean required, or unable to be done without.
• Potential means possible rather than required, which is why it does not fit.
• Necessary is spelt with one c and a double s.

Common traps

• Answering on the -tial ending instead of on meaning.
• Misreading existential as essential at speed, since the two look alike.
• Rejecting essential as too easy and looking for a harder-sounding option.

No directly related past PYQ was found.