how long did it take to make this mover a.12yrs b.16 yrs or c.14yrs

If you mean SCREAM 4... SCREAM 3 was released in 1999 or something, so it can't be mais than 12 years. But I seriously doubt Kevin Williamson started to plan a fourth immediately after, so... I'd say much less than 12 years.

As for the original SCREAM, I don't think there's any official information on that, so I don't know where did you get those numbers?

Scream was made in '96.
Scream 2 was made in '97.
Scream 3 was made in '00.
Scream 4 was made in '11.
I know how long it took to make 2, 3, and 4. But I don't know how long it took to make 1.