The correct option is C Section C
Consider, the total number of students is 100, which signifies the whole pie.
So, in the given circle graph or pie chart,
∙ number of students in section A= 21 (blue portion)
∙ number of students in section B= 36 (green portion)
∙ number of students in section C= 16––– (orange portion)
∙ number of students in section D= 27 (yellow portion)
∴ Section C has the least number of students.