A botanist selects n^2 trees on an island and studies (2n + 1) trees everyday where n is an even integer. He does not study the same tree twice. Which of the following cannot be the number of trees that he studies on the last day of his exercise?
A. 13
B. 28
C. 17
D. 31
E. 79![]()
A. 13
B. 28
C. 17
D. 31
E. 79