Choose one word that substitutes the highlighted words.

The by-products of this experiment could be poisonous or unhealthy. 

Toxic 

The correct answer is Option (3) → Toxic

The word that best substitutes the highlighted words is toxic.

• Torpid means slow-moving or inactive.
• Tragic means causing great suffering or sorrow.
• Toxic means poisonous or harmful.
• Trivial means of little importance or consequence.