Question

Assertion :The life span of a domestic dog is about 20 years. Reason: The life span of laboratory mouse is 4.5 years.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

The maximum life span is a characteristic of the species. It is the maximum number of years a member of that species has been known to survive. The maximum life span of a domestic dog is about 20 years, and that of a laboratory mouse is 4.5 years. The life expectancy of dogs depends on a dog's size. The aging profile of dogs varies according to their adult size. A larger dog's heart has to work much harder to support the dog's organs than that of a little dog. Other factors contributing to a dog's life expectancy is overall health and lifestyle. However, a dog cannot expect to live 20 years, and most mice 4.5 years. The life expectancy, the amount of time a member of a species can expect to live, is not characteristic of species, but of populations. It is usually defined as the age at which half the population still survives.

Thus, the correct answer is option B.