Proper collimation of the useful beam for the film size and target-film distance will reduce
1. intensity of central beam.
2. secondary radiation.
3. radiographic contrast.
4. image definition.
5. radiation received by patient.

(2) (3) (4) (5)

(1) (2) (3) (5)

(1) (3) (4) (5)

All of the above.

(2) and (5)