Correct the phrase written in parentheses

Because the starfish depends on its (arms, for mobility and defense, this strategy) effectively incapacitated him, rendering him helpless to fight off the persistent spiny army.

Select one answer
A
NO CHANGE
B
arms, for mobility and defense this strategy
C
arms for mobility and defense, this strategy
D
arms for mobility and defense this strategy

C: arms for mobility and defense, this strategy