Question

read the passage. then answer the question below.
a dock in the red sea in egypt provides a place for boats to tie up. it is also a habitat for many marine organisms. small silverside fish shelter in the shadows below the dock, hiding from larger fish.
seaweed and invertebrates, such as corals and sponges, grow on the wooden posts that support the dock. sponges are filter feeders. they feed by filtering microscopic algae and small animals out of the salt water.
beneath a boat dock in the red sea, the silversides, the sponges, and the salt water make up which of the following? select all that apply.
a population
part of a community
part of an ecosystem

Explanation:

• Population: A population consists of individuals of the same species. Here, the silversides alone could be a population (but the question says "the silversides, the sponges, and the salt water"—this part might be a mis - understanding. However, if we consider each group (e.g., all silversides as a population), but more accurately, when combined with non - living (salt water), it's not a pure population. But if we assume the question is about the biological components in a general sense (a wrong assumption but trying to fit), or if we consider that maybe there was a mis - phrasing and it's about the biological entities (silversides as a population).
• Community: A community is all the different species of organisms in an area. The silversides and sponges (along with other organisms like corals etc. implied) are part of a community.
• Ecosystem: An ecosystem includes all the living organisms (biotic factors like silversides, sponges) and the non - living components (abiotic factors like salt water) in an area.

Answer:

B. part of a community, C. part of an ecosystem