A block is released from rest at the top of an inclined plane which later curves into a circular track of radius `r` as shown in figure. Find the minimum height `h` from where it should be released so that it is able to complete the circle.
A. `h lt 5r//2`
B. `h gt 5r//2`
C. `h= 5r//2`
D. `h ge 5r//2`
