Language Conventions

Which of these fits gap 17?

Directions: Complete this passage by selecting the most suitable option for the corresponding gap.

Our body _____ (17)______ its support from this strong frame made of bones called skeleton.
The place where two bones _____ (18) _______ each other is called a bone joint.
Bones are _______(19)_______  with a rubbery substance called “cartilage” at the joints.
Bones are five times _____(20)_____ than steel