This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to know if your dog is losing its eyesight
Look for cloudy pupils.
When a dog's vision begins to suffer with age, you may notice a change to the eye color itself. Cataracts are often a cause of loss of vision related to age, and can be easily seen by looking at your dog's eyes.

Choices:
[+] Your dog may also be looking at its corneas, which are the watery areas inside. However, cataracts are usually uncommon in older dogs, especially german shepherds.
[+] Normal eyes may begin to blink brightly for a few seconds and then gradually darken again or lose their whites completely. Cataracts often occur if you pet your dog constantly.
[+] Cataracts are marked by a cloudy appearance around a dog's pupil. Monitor your dog's eyes frequently as it ages, as cataracts are easier to treat and reverse if caught early.
[+] When a dog develops cataracts, the color becomes darker and take on a bluish complexion. Peripheral peripheral vision in older dogs may also manifest in a bluish complexion.
The answer is:
Cataracts are marked by a cloudy appearance around a dog's pupil. Monitor your dog's eyes frequently as it ages, as cataracts are easier to treat and reverse if caught early.