The options seem a bit mis-formatted but here is the way p is computed:
the decrease is 2000-1600
and it is relative to: 2000 (2003 attendance)
so 
and so that aligns with your Option A. Options B, C, D look incorrect for sure.
Estimate: 331,000
sum: 331,200
Answer:
c
Step-by-step explanation:
25% 3/10 1/3 and 37.5%
.25,.30,.33,.375
This question is based on least common multiple method.
As given in the question,
Aunts are taking pictures in group of = 5
Uncles are taking pictures in group of = 10
So we have been asked what is the minimum number of aunts Sana have.
As we have been given that the number of aunts and uncles is equal so to find the minimum number of aunts we will apply the least common multiple method.
So we get LCM of 5,10 as 10
Hence there are minimum 10 aunts.