Which of the following is not categorised under narrowly utilitarian…

The correct answer is Option (3) → Oxygen

Option (1) Food — Narrowly utilitarian.

Option (2) Fibres — Narrowly utilitarian.

Option (3) Oxygen — Not narrowly utilitarian. Oxygen from plants is an ecosystem service, a broadly utilitarian benefit.

Option (4) Construction material — Narrowly utilitarian.

NCERT Extract:
Why Should We Conserve Biodiversity? – “… The narrowly utilitarian arguments for conserving biodiversity are obvious; humans derive countless direct economic benefits from naturefood (cereals, pulses, fruits), firewood, fibre, construction material, industrial products (tannins, lubricants, dyes, resins, perfumes ) and products of medicinal importance. More than 25 per cent of the drugs currently sold in the market worldwide are derived from plants and 25,000 species of plants contribute to the traditional medicines used by native peoples around the world. Nobody knows how many more medicinally useful plants there are in tropical rain forests waiting to be explored. With increasing resources put into ‘bioprospecting’ (exploring molecular, genetic and species-level diversity for products of economic importance), nations endowed with rich biodiversity can expect to reap enormous benefits.”
Why Should We Conserve Biodiversity? – “… The broadly utilitarian argument says that biodiversity plays a major role in many ecosystem services that nature provides. The fast-dwindling Amazon forest is estimated to produce, through photosynthesis, 20 per cent of the total oxygen in the earth’s atmosphere.”