The correct choice that indicates \( AB \) is the perpendicular bisector of \( CD \) if they intersect at \( P \) is:
AB⊥CD and CP≅DP
This means that line segment \( AB \) is perpendicular to line segment \( CD \), and the lengths of segments \( CP \) and \( DP \) are equal, confirming that \( P \) is the midpoint of \( CD \).