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The human eye is like a camera that has a lens with:

Options

  1. Afixed focal length and fixed asperture size.
  2. Bvariable focal length and fixed aperture size.
  3. Cfixed focal length and variable aperture size.
  4. Dvariable focal length and variable aperture size.

Correct answer

D. variable focal length and variable aperture size.

Step-by-step solution

Variable focal length and variable aperture size: This option means that both the focal length and the aperture size can change. The human eye indeed has a variable focal length (accommodation allows it to focus on objects at varying distances) and a variable aperture size (pupil dilation adjusts based on light conditions).

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