a or the?

[nado92]

Healthy diet of fruit and vegetables could prevent ..........disease.
a) A
b) the
c) no article

I may choose 'a'.
It is my opinion. But I am not sure.

 

[emsr2d2]

Healthy diet of fruit and vegetables could prevent ..........disease.
a) A
b) the
c) no article

I may choose 'a'.

It is my opinion. But I am not sure.

It's "c" - no article. Disease is used here as a collective noun for all/various diseases. However, I would argue that "A" is required before the word "Healthy".