Which of the Following Statements About the Heapsort Algorithm Is

Multiple Choice

Which of the following statements about the heapsort algorithm is correct?

A) The heapsort sorts an array that is already sorted in O(n) .
B) The heapsort algorithm is based on inserting elements into a heap and removing them in sorted order.
C) Each insertion and removal is O(n log(n) ) .
D) The heapsort algorithm requires more space than the mergesort.