Given code segment:
The code segment given is:

for(i = 1; i ≤ n; i++) {
fork();
}

This code segment contains a for loop that iterates from i = 1 to i ≤ n, and for each iteration, it creates a new process using the fork() system call.

Explanation:
Let's analyze the code segment step by step to understand how many new processes are created.

1. Initial iteration (i = 1):
- The first fork() call creates a duplicate process (child process) from the original process (parent process).
- Now, there are two processes (parent and child).

2. Second iteration (i = 2):
- Both the parent and child processes from the previous iteration continue executing the code segment.
- Now, both the parent and child processes execute the fork() call, resulting in each process creating a new child process.
- So, for each of the two processes, two new processes are created.
- Now, there are four processes (two parents and two children).

3. Third iteration (i = 3):
- All the processes from the previous iteration (four processes) execute the fork() call.
- Each process creates a new child process, resulting in eight processes.
- Now, there are eight processes (four parents and four children).

4. Similarly, for the remaining iterations (i = 4 to i ≤ n):
- The number of processes doubles for each iteration.
- For each iteration, the number of processes created is equal to the previous number of processes multiplied by 2.

Total number of processes created:
The total number of processes created can be calculated by summing the number of processes created at each iteration.

Let's consider the number of processes created at each iteration for simplicity:

- Iteration 1: 2 processes
- Iteration 2: 2 * 2 = 4 processes
- Iteration 3: 2 * 2 * 2 = 8 processes
- Iteration 4: 2 * 2 * 2 * 2 = 16 processes
- Iteration 5: 2 * 2 * 2 * 2 * 2 = 32 processes

We can observe a pattern here: the number of processes doubles with each iteration.

So, the total number of processes created is given by the formula: 2^n, where n is the number of iterations (n = 5 in this case).

Therefore, the correct answer is option 'C' - 2n - 1, which is equal to 2^5 - 1 = 32 - 1 = 31.