PCAP Exceptions and File I/O Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  KeyboardInterrupt inherits from BaseException.

  Why this is correct

  KeyboardInterrupt is a true statement because KeyboardInterrupt is a direct subclass of BaseException, not of Exception. This design ensures that a KeyboardInterrupt triggered by Ctrl+C propagates outward even when code has a broad `except Exception:` handler. Catching it accidentally would prevent clean interruption and could leave the program in an inconsistent state, so it must be caught explicitly with `except KeyboardInterrupt` or a bare `except:`. The hierarchy deliberately places user-initiated termination outside the ordinary exception family.

• ✓

  SystemExit inherits from BaseException.

  Why this is correct

  SystemExit is also a true statement because SystemExit inherits directly from BaseException, bypassing Exception. It is raised by `sys.exit()` to request interpreter shutdown, and by keeping it outside Exception, Python prevents generic exception handlers from swallowing exit requests. A bare `except Exception:` will not intercept SystemExit, allowing cleanup and termination logic in `finally` blocks to run as intended. This separation reflects that SystemExit is not an application error but a controlled exit mechanism.

• ✗

  IOError is a separate class from OSError.

  Why it's wrong here

  IOError is a separate class from OSError is false because in Python 3, IOError is simply an alias for OSError, not a distinct class. Both names refer to the exact same class object, so code using either name catches identical exceptions. This unification happened in Python 3 (and was already the case in Python 2 for practical purposes) to streamline operating-system-related error handling. Treating them as separate would misrepresent the modern exception hierarchy where the name IOError exists only for backward compatibility.

• ✓

  ZeroDivisionError inherits from ArithmeticError.

  Why this is correct

  ZeroDivisionError is a true statement because ZeroDivisionError inherits from ArithmeticError, which in turn inherits from Exception. ArithmeticError groups numeric errors like integer division by zero, overflow, and floating-point failures under one common parent. Since ArithmeticError is a subclass of Exception, ZeroDivisionError is catchable by a general `except Exception:` handler, making it a standard runtime error rather than a system-level interruption. This placement allows programmers to handle all arithmetic failure modes uniformly while still being able to catch more specific subclasses separately.

• ✗

  GeneratorExit inherits from Exception.

  Why it's wrong here

  GeneratorExit is a false statement because GeneratorExit inherits directly from BaseException, not from Exception. This exception is raised when a generator's `close()` method is called, signaling that the generator should exit from its current suspension point. By placing GeneratorExit outside Exception, Python prevents ordinary `except Exception:` blocks inside the generator from unintentionally catching the exit signal and continuing execution. The generator must either re-raise it or let it propagate to properly shut down, distinguishing it from regular runtime errors.

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