Final answer:
The correct answer is B. The z-score for the lower quartile of a normal distribution is approximately -0.67, corresponding to the 25th percentile of the data.
Step-by-step explanation:
The z-score for the lower quartile of any normal curve, which is the first quartile (Q1) or the 25th percentile, is approximately -0.67. This is because the lower quartile divides the bottom 25% of data from the top 75%.
Since the normal distribution is symmetric, the value on the z-table that corresponds to an area of 0.25 (or 25% of the area under the curve to the left of the z-score) is a negative z-score.
Looking up the values in a standard normal distribution table or using standard statistical software, we can find the z-score that leaves 25% of the distribution to its left, which is approximately -0.67.