Which of the following is true about control charts? Which of the following is true about control charts? As the sigma level for a control chart increases, the UCL and LCL get closer together As the sigma level for a control chart increases, the LCL and UCL get farther apart Sigma levels have no effect on the UCL or LCL Sigma levels cannot be changed As the sigma level for a control chart increases, the process becomes more capable of meeting a customer's specification