The question is asking about a key factor in the development of expert performance. Research has consistently shown that 'intensive practice' is a critical factor in achieving expert performance, making B the correct answer. Option A, 'natural talent,' can be a component but is not the sole or most significant factor. Option C, 'proper nutrition,' is important for overall health and performance but is not the key factor in developing expertise. Option D, 'socioeconomic status,' can influence access to resources but is not a direct factor in the development of expert performance. The correct answer is B.