Most invasive species are neither terribly successful nor very harmful. Britain's invasive plants are not widespread, not spreading especially quickly, and often less of a nuisance than vigorous natives such as bracken. The arrival of new species almost always increases biological diversity in a region; in many cases, a flood of newcomers drives no native species to extinction. One reason is that invaders tend to colonise disturbed habitats like polluted lakes and post-industrial wasteland, where little else lives. They are nature's opportunists.

Correct Option (C)

The passage challenges the common assumption that invasive species are universally harmful. It highlights that most invasive invasive species are neither significantly successful nor detrimental, often increasing biodiversity without driving native species to extinction. Furthermore, they frequently colonise disturbed habitats where native life is sparse. This suggests that the perceived threat of foreign plants may be exaggerated in certain contexts, implying that campaigns against them might sometimes lack justification or be ineffective.

Incorrect Options:

Option (A) is incorrect because the passage observes that invasive species tend to colonise disturbed habitats naturally; it does not advocate for their deliberate use in rehabilitation efforts for desert areas or wastelands. The passage describes an observation, not a prescriptive solution.

Option (B) is incorrect because the passage offers a nuanced perspective on the impact of invasive species, suggesting that concerns might sometimes be exaggerated. It does not argue for the complete abolition of all laws or regulations concerning the introduction of foreign plants, which would be an extreme interpretation beyond the scope of the passage.

Option (D) is incorrect because while the passage states that the arrival of new species almost always increases biological diversity, it presents this as an observed outcome rather than a recommendation for actively introducing foreign plants to enhance biodiversity. The passage does not endorse such a policy.