Final answer:
Option B, which is the for loop written as for(; ;), is an infinite loop because it has no terminating condition, initialization, or change in variables within the loop structure. Options C and D are also potentially infinite, but Option B is the most classic representation of an intentional infinite loop.
Step-by-step explanation:
The student has asked to identify the infinite loop from a given set of loops. When looking at the options, we need to consider the initialization, condition, and increment/decrement parts of a for loop.
Option B: for(; ;) is an infinite loop. It has no initialization, no terminating condition, and no increment/decrement. Since there's nothing to stop this loop from running, it will continue indefinitely unless broken by an outside force (like a break statement or external interruption).
Option C: for(int I = 0; I < 1; I--) is not an infinite loop because it will run only once. The variable I is initialized to 0 and the loop runs while I is less than 1. After the first iteration, I is decremented to -1, which does not satisfy the condition I < 1, thus the loop ends.
Option D: for(int I = 0; ; I++) is also an infinite loop, as there is no terminating condition specified. The variable I will increment indefinitely, and there's nothing in the loop structure to stop it from doing so.
However, the answer to this question, according to the way it's structured, is Option B because it is the most cleanly represented infinite loop, typically used when an infinite loop is intentionally designed.