Concept:To find the smallest value, evaluate each expression step by step and compare the results.Explanation:Option A: 3670+800+20=4490Option B: 3955+601−80=4476Option C: 4500−128+40=4412Option D: 4600−150−29=4421Compare the four numbers: 4412 is the smallest among 4490, 4476, 4412, and 4421.Answer:Option C: 4500−128+40