Fishes are poor bioindicators of the environmental health of an aquatic system.
a. true
b. false

b. False

Explanation:

Bioindicators are species, species groups or biological communities whose presence, abundance and conditions are biological indicative of a particular environmental condition. Bioindicators are important to correlate with a particular anthropogenic factor or a potentially impacting natural factor, representing an important tool in assessing the ecological integrity (health status of an area, defined by comparing the structure and function of a biological community between a impacted area and reference areas).

Contamination of aquatic environments and water for public use becomes a growing problem as human population growth expands, as does the demand for sufficient and quality water. Fish are very sensitive to contamination of aquatic environments and are therefore strong bioindicators of the environmental health of an aquatic system.

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

hope it ,

bioteacher101