[单选题]
The pupil of a person's eye ch kqoj.s490r ;gycjw,) kxb( lzb2ow. vanges from a diameter of 3.5 mm to 1.5 mm as the dipy5hr kl(yk)pyp8r7j4s *t.-e y6s illumination is increased. By what factor does the my5rj spy)kpyr8yh4dke( ls7.p 6 -*itinimum angle of resolution change?