Sara Has Been Asked to Perform a Port Scan on a Number

Sara has been asked to perform a port scan on a number of servers to check for access points that should not be running but would have elevated privileges. She is not familiar with port numbers and isn't sure how to scan only those that we know meet the scanning criteria. What advice would you give her?

A) She should scan 1-1023
B) She should scan 0-63535 just to be sure
C) She should scan 1-49151
D) She should consult the network documentation and avoid the scan altogether.