Which row of the table shows the response of the iris to reducing levels of light?

Answer:

19) C

This is no longer on the BMAT syllabus.

However, you should have been able to at least eliminate options A and D.

This is because when levels of light are reducing, the pupil would get bigger (dilated) to allow more light to enter the eye.

To allow the pupil to dilate, the radial muscles need to contract and the circular muscles need to relax.