Question

which of the following traits is most likely affected by environmental factors?
a changes in the number of chromosomes
b having a genetic disease since birth
c blood types being different among different people
d skin tone changes due to sun exposure

Explanation:

To determine the trait affected by environmental factors, we analyze each option:

• Option a: Changes in chromosome number are genetic (mutation - related), not environmental.
• Option b: Genetic diseases from birth are due to genetic inheritance, not environment.
• Option c: Blood types are determined by genetics (ABO system, etc.), not environment.
• Option d: Sun exposure (an environmental factor) causes skin tone changes, so this trait is affected by the environment.

Answer:

d. Skin tone changes due to sun exposure