Final answer:
To make the bright spots of the wave pattern appear closer together on the optical screen, one would need to decrease the distance between the two slits.(option B)
Step-by-step explanation:
To make the bright spots of the wave pattern appear closer together on the optical screen, one would need to decrease the distance between the two slits. This is because when the slits are closer together, the waves passing through them interfere with each other more, creating a smaller distance between the bright spots.
For example, if you decrease the distance between the two slits, the interference pattern will have narrower bands and the bright spots will appear closer together on the optical screen.
So, the correct answer is B. Decrease the distance between the two slits.