Question

Arthropods have not been able to achieve great size because
(1) the type of organ systems they possess could not support·such a development
(2) they would be unable to successfully reproduce
(3) chitin is brittle and must be thick to bear the pull of muscles
(4) their vision is not good enough to hunt larger prey

My attempt:

https://i.stack.imgur.com/S456T.png

Answer 1

3. chitin is brittle and must be thick to bear the pull of muscles