Biology

The correct answer is: D.All of the above are reasons for concern.

Each of the listed phenomena is a reason why scientists are concerned about human impact on Earth's carrying capacity:

A. Bee colonies dying off due to pesticide use: Bees play a crucial role in pollination, and their decline threatens ecosystems and agriculture, affecting food production and biodiversity.

B. Poisonous algae proliferating and excreting toxins into lakes and rivers: This can lead to the depletion of water quality, harming aquatic ecosystems and ma...