Why is bioleaching considered an alternative method of metal extraction?

The correct option is It is more environmentally friendly than traditional methods. This answer is correct because it matches the approved learning objective to describe bioleaching as using bacteria to produce leachate solutions containing metal compounds. (HT only) in the subtopic Alternative methods of extracting metals.

The correct option is It is more environmentally friendly than traditional methods. It is more environmentally friendly than traditional methods is correct because it directly supports the approved learning objective to describe bioleaching as using bacteria to produce leachate solutions containing metal compounds. (HT only). This belongs to the subtopic Alternative methods of extracting metals within Using the Earth's resources and obtaining potable water, so the explanation must stay tied to that curriculum context. The other options are incorrect because they either do not answer this learning objective, use a vague statement, or move away from Alternative methods of extracting metals.