The IKEA effect means that labor will increase people's feelings about the fruits of labor. When people make things by themselves, they will find their creations particularly valuable. Based on the above definitions, which of the following best reflects the IKEA effect? ['Let people make origami by themselves, and then bid together with origami made by others. As a result, everyone is willing to pay a higher price for the origami they make.', 'In order to make cakes for the convenience of a company, a company introduced convenient cake flour to make cakes very simple.', 'The furniture produced by a furniture manufacturer requires the customer to buy the home and complete the assembly and assembly of the home according to the product manual.', "The school encourages students to make various teaching aids by themselves, which not only exercises the students' practical ability, but also saves teaching costs."]