A diffraction pattern is created on a screen when blue light is passed through a single slit. Does the central bright maximum in this pattern become wider or narrower, when the blue light is replaced by red light?

becomes wider

Explanation:

From;   asin θ= m λ

It was said in the question that in this particular instance  blue light is replaced by red light. The wavelength of blue light is less than that of red light, it then follows that the central bright maximum in this pattern widens when red light is used.

Therefore the diffraction pattern becomes wider.

think its the third option

the area between the graph and the t axis