Read the passage. Adapted passage: Researchers studying a preference for sweet food found that heredity may influence how strongly sweetness is experienced. In animal studies, receptors send signals about sweetness to the brain. Environment still matters: people who gradually reduce added sugar can become accustomed to less sweetness. Doctors caution against simply disabling a “sweet” mechanism because naturally sweet foods can also provide useful energy and nutrients. Artificial sweeteners therefore do not make the biology of taste irrelevant. Which statement best reflects the passage’s view of heredity and environment?

1. Only heredity matters
2. Only environment matters
3. Neither heredity nor experience affects taste
4. Heredity may influence sweet preference, but experience and diet can also modify it