You Are Parsing a Log File That Contains Three Columns

Multiple Choice

You are parsing a log file that contains three columns: a timestamp, an account number (a string) , and a transaction amount (a number) . You want to calculate the sum of all transaction amounts for each unique account number efficiently. Which data structure should you use?

A) A linked list
B) A hash table
C) A two-dimensional array
D) A comma-delimited string