Question

despite their efficiency, what environmental concern is raised about compact fluorescent bulbs? excessive brightness mercury content and disposal too efficient

Explanation:

Compact fluorescent bulbs (CFLs) contain mercury, a toxic substance. Improper disposal (like throwing them in regular trash) can release mercury into the environment, contaminating soil, water, and air. "Excessive brightness" is not an environmental concern related to their nature, and "too efficient" is illogical as efficiency is a positive trait, not an environmental concern. So the correct concern is about mercury content and disposal.

Answer:

B. mercury content and disposal (assuming the options are labeled A, B, C with A: excessive brightness, B: mercury content and disposal, C: too efficient)