Euphorbia esula (leafy spurge) is a Eurasian plant that has become invasive in North America, where it displaces native vegetation and sickens cattle. E. esula can be controlled with chemical herbicides, but that approach can also kill harmless plants nearby. Recent research on introducing engineered DNA into plant species to inhibit their reproduction may offer a path toward exclusively targeting E. esula, consequently ______
Which choice most logically completes the text?
Explanation
Context: E. esula is an invasive plant. Chemical herbicides can control it but kill nearby harmless plants too. Research on engineered DNA to inhibit E. esula's reproduction offers a targeted alternative. The blank states the consequence of this targeted approach.
Answer: D) reducing invasive E. esula numbers without harming other organisms.
Why? The passage explicitly contrasts the new DNA approach with herbicides that kill harmless plants nearby. The targeted DNA method would reduce E. esula specifically — D states this selective benefit.
Traps:
- A) making individual E. esula plants more susceptible to existing chemical herbicides → about herbicide use, not the DNA targeting approach
- B) enhancing ecological benefits of E. esula → E. esula is invasive and harmful; there are no ecological benefits to enhance
- C) enabling cattle to consume E. esula without becoming sick → about cattle health, not plant population control