[Vocabulary] distinct/distinguished

[Silverobama]

Hi,

The patterns of spoken language are _______ from those of writing.

a)distinct
b)distinctive
c)distinguished
d)distinguishing

Why the answer is "a"?

 

[Raymott]

Hi,

The patterns of spoken language are _______ from those of writing.

a)distinct
b)distinctive
c)distinguished
d)distinguishing

Why the answer is "a"?

That's the word that fits the question best. "A is distinct from B" - A is different from B. Spoken and written patterns are distinct.
Both patterns could be called "distinctive", but A is not distinctive from B.
A can be distinguished from B, but I don't think that's what the question means. Although c) is possible.
d) is wrong.