'Permaculture', a term often seen in the news, pertains to:

Correct — D. Permaculture is a way of designing farms and settlements on the pattern of flourishing natural ecosystems, so that they sustain themselves.

The word comes from permanent agriculture and was coined in 1978 by Bill Mollison and David Holmgren in Australia. Sustainable agricultural ecosystems → option (d).

Why the others are wrong

• (a)
  Cropping and vegetation in permafrost regions. — Perma- here means permanent, not permafrost. Permafrost is ground that stays frozen for two or more years, and permaculture has nothing to do with farming on it.
• (b)
  Ex-situ growth of organisms facilitated in a semi-solid medium. — Growing cells or tissue outside the organism on a semi-solid medium such as agar is plant tissue culture, a laboratory technique, not permaculture.
• (c)
  A bioremediation technique to remove oil spills. — Cleaning up oil spills with microbes is bioremediation. It is a technique for treating polluted sites, not a system for designing farms.

Permaculture treats a farm as an ecosystem. Plants, animals, water and soil are arranged so that each supports the others: a hedge breaks the wind, fallen leaves feed the soil, a pond stores rain.

The goal is a system that keeps producing with few outside inputs such as fertiliser and pesticide. That places it beside organic farming and agroecology in discussions of sustainable agriculture.

Key facts

• The term permaculture was coined in 1978 by Bill Mollison and David Holmgren in Australia.
• Permaculture is a contraction of permanent agriculture.
• Permafrost is ground that remains frozen for at least two consecutive years.

Common traps

• Reading perma- as permafrost: the prefix comes from permanent.
• Confusing permaculture with tissue culture because both end in culture: tissue culture is a laboratory technique on a nutrient medium.

No directly related past PYQ was found.