After looking at the effect of sample size on standard error of the mean, assuming the same population standard deviation, what is the best conclusion? a. increasing sample size leads to a dramatic reduction in the standard error at first, but the benefits of increasing sample size on standard error are reduced as sample size is increased. b. increasing sample size leads to a dramatic increase in the standard error at first, and increasing standard error leads to sample means that are closer to the population mean. c. increasing sample size increases the standard error of the mean; therefore, it is best to use as small a sample as possible in order to minimize data collection and analysis costs. d. increasing sample size has no effect on the magnitude of the standard error; therefore, using a very small sample size is preferable in order to minimize data collection and analysis costs.