Question

3. They have finally (a) ............... it. For years scientists debated whether the sound of crackling
knuckles came (b).................... bubbles being formed in the fluid around our joints (c). ..from
bubbles popping. But now a study (d) ... ........... found that the tiny bubbles make (e) .....
popping sound when they only partially collapse.

Answer 1

Answer:

solved, from, or, has, the

Answer 2

a) researched/found

b) from

c)or

d)has

e)the