The achievements of the team have been monumental in the last ten years.

Correct — D, unimpressive. Applied to achievements, 'monumental' means great enough to stand out and be remembered, so the reverse is work that makes no impression at all. Enormous, memorable and striking each praise the achievements in their own way; only 'unimpressive' withholds the praise.

Why the others are wrong

• (a)
  enormous — 'Enormous' means very large in size or degree — a synonym of 'monumental' in this use, not its opposite.
• (b)
  memorable — 'Memorable' means worth remembering, which is part of what 'monumental' claims, so it points the same way.
• (c)
  striking — 'Striking' means noticeable and impressive, echoing 'monumental' instead of reversing it.

An antonym item on 'monumental' used figuratively of achievements — outstanding in scale or importance — whose reverse is 'unimpressive'.

Key facts

• Figuratively, 'monumental' means outstanding in size, extent or importance.
• It also has an ironic use for a very large mistake, as in a monumental blunder.
• Its nearest opposites are unimpressive, trivial, insignificant and paltry.

Common traps

• Choosing 'enormous' because it matches the size idea rather than reversing it.
• Treating the item as a synonym question when three of the options are synonyms.

No directly related past PYQ was found.

• practice — not a real PYQ

  Select the word opposite in meaning to 'colossal'.

  • (a)gigantic
  • (b)vast
  • (c)tiny
  • (d)immense
  Answer(c) tiny — colossal means extremely large, so the reverse is extremely small; the other three are synonyms.
• practice — not a real PYQ

  Select the word opposite in meaning to 'remarkable'.

  • (a)notable
  • (b)ordinary
  • (c)striking
  • (d)extraordinary
  Answer(b) ordinary — what is remarkable stands out, and what is ordinary does not.