Answer:
C. normal
Step-by-step explanation:
given that samples of size n=600 are taken from a telephone survey and the mean age is taken from each sample.
Here we find that sufficiently large sample sizes are taken and can be assumed random as taken as per survey
Recall central limit theorem
The sample mean for large samples randomly drawn will follow normal distribution irrespective of the original distribution of the variable
Hence here we get normal distribution
Option c is right
C. normal