A summer camp that offers one-week programs faces the challenges of long queues as parents try to check in their children each Saturday morning. If they were to add more staff to assist with the check-in process, then which of the following will occur? 

i. The average time parents wait decreases. 

ii. The maximum time the parents wait decreases. 

iii. The average number of parents waiting to check in their child decreases. 

a. Just I 

b. Just II 

c. Just III 

d. I and II 

e. I and III 

f. II and III 

g. I, II, and III