The Algae Caulerpa Taxifolia Is Native to Warm Tropical Waters

The algae Caulerpa taxifolia is native to warm tropical waters. However, a cold-tolerant strain was selectively bred for aquariums and as a result, it has become an invasive species in the Mediterranean where it grows in much colder water than its native range. Which of the following factors did humans have the greatest impact on?

A) We altered species interactions within the local community of the Mediterranean.
B) We changed the environmental tolerances of the specific strain of algae to suit the Mediterranean.
C) We increased the dispersal ability of the specific strain of algae from their regional species pool.
D) We changed the regional species pool from where the algae were native.