Brad's teacher dropped a whole box of metal tacks onto the floor. His teacher then shares with the class that they will participate in a design challenge. Brad's teacher explains the criteria and constraints for the design challenge. Each team is challenged to design a device to try to pick up as many of the tacks as possible. The design can contain only one magnet. Each team will get only one pass of their device over the tacks. The team that picks up the most tacks will win the design challenge. Brad's team has several ideas for a winning design. Evaluate who has the idea for the kind of magnet that will MOST LIKELY pick up the most tacks.
A) Mary thinks they should use a bar magnet.
B) Paul thinks they should use a ceramic magnet.
C) Michael thinks they should use an electromagnet.
D) Kelly thinks they should use a horseshoe magnet.