Answer:
a. $175,000
Step-by-step explanation:
Given that 
Purchased share = 2,500 
Stock = $180,000 
So, Joe's basis receives stock of Pete Moss is $175,000 and when stock is transmitted heritable from another person, the value of stock transfer after the death of the person. 
Since, Pete Moss is died on 23 July and on that day the stock was $175,000. So, Joe receive stock $175,000.
Hence the correct option is a. $175,000