Read the original ACT Reading-style passage, then answer the question. The Artificial Reef: Engineers sink concrete forms offshore to create an artificial reef. Early reports count fish around the forms and declare success. A marine ecologist asks which fish have arrived: species displaced from nearby rocks or juveniles finding shelter where none existed before. The count alone, she argues, cannot distinguish attraction from production. Her question changes the event from a celebration of numbers to an inquiry about ecological effect. What conclusion about the ecologist's concern is best supported?