The correct answer is C. Both (a) and (b).
A race condition is a situation in which the outcome of a computation depends on the order in which multiple operations are performed. This can happen when multiple threads or processes are accessing and modifying the same data at the same time. If the order of these operations is not controlled, it can lead to unexpected results.
For example, let's say we have a bank account with a balance of \$100. Two users, Alice and Bob, are both trying to withdraw \$50 from the account. If Alice's transaction is processed first, the balance will be \$50 after her transaction is complete. Then, when Bob's transaction is processed, the balance will be \$0, and Bob will get an error message. However, if Bob's transaction is processed first, the balance will be \$50 after his transaction is complete. Then, when Alice's transaction is processed, the balance will be \$0, and Alice will get an error message.
In this example, the outcome of the transaction (whether Alice or Bob gets the money) depends on the order in which the transactions are processed. This is a race condition.
Race conditions can be avoided by using synchronization mechanisms, such as locks, to ensure that only one thread or process can access a particular piece of data at a time.