1. Split queries are a type of inference attack where multiple queries are used to infer some information that was meant to be protected. For example, an adversary can issue a query requesting the average age of all employees with the role of CEO, knowing that only one such employee exists. The adversary then issues a query requesting the maximum salary of all employees of that particular age. The adversary can now conclude with reasonable confidence that he has successfully deduced the salary of the CEO. Which of the following would help prevent an inference attack in such a scenario?

1. not allow aggregate query results when the set of tuples selected is too small or below a threshold.
2. Transform the database by removing name information of the employees from the database records.
3. Ensure related queries are always processed as a single transaction.
4. All of the above

2. Which of the following is TRUE about rootkits (select all that apply)?

1. Rootkits can modify the function parameters and return values of a system call.
2. The original system call function is never executed after the rootkit replaces it in the system call table.
3. Rootkits that hook the system call table execute in kernel mode, not user mode.

3. Which of the following is/are TRUE regarding the "Nansh0u" malware (discussed in: https://thehackernews.com/2019/05/hacking-mysql-phpmyadmin.html).

1. It is a virus
2. It is a worm
3. It is a rootkit
4. It is a cryptojacking malware