Question

question 9 (1 point)
kelp
supports itself with gas filled floats
attaches itself to the ocean bottom
all of the above are correct.
is abundant in coastal upwelling zones

Explanation:

Kelp uses gas-filled floats (pneumatocysts) to keep its blades near the surface for photosynthesis, attaches to the ocean bottom via holdfasts, and thrives in coastal upwelling zones rich in nutrients. Thus, all statements are correct.

Answer:

all of the above are correct.