Answer:
C.) 13
Step-by-step explanation:
So, I'm going to break this down to the three sentences. If you look at the key words in each sentence, grammatically the last one stands out.
In the first sentence it is saying Jessie HAS 8 more pencils than Dylan
In the second sentence it is saying Together they HAVE a total of 18 pencils
In the third sentence it is asking How many pencils DID Dylan have
The word MORE implies in addition to. And this very well could mean at least. I believe the answer is 13.
Saying Dylan had 5 pencils (+ J's 8), would be 13
Saying Dylan had 8 pencils (+J's 8), would be 16
Both of which are not AT LEAST 18
Saying Dylan had 13 pencils (+J's 8), would be 21
If 10 is incorrect, your answer should be 13