Question

Read the passage "Salmon Reproduction" in the box below.

SALMON REPRODUCTION

Salmon are born in freshwater streams, then swim out to the ocean. They spend anywhere from one to five years in the ocean before maturing enough to mate. When it is time, the salmon swim upstream, back to the place where they were born, to mate and lay their own eggs.


If humans build a dam across a stream, how will this most likely affect the salmon that need to cross the dam?
A.
It will make the salmon population go down, as they can't mate and lay eggs.

B.
It will make the salmon population fight against each other for breeding grounds.

C.
It will make the salmon lay their eggs in the ocean to ensure successful reproduction.

D.
It will make the salmon lay their eggs in front of the dam, clogging path's downstream

Answer 1

A. It will make the salmon population go down, as they can't mate and lay eggs.

Explanation: Salmon must return to freshwater streams where they were born to spawn. A dam blocks their upstream migration, preventing them from reaching suitable spawning sites and reducing successful reproduction, causing population declines.