Read the passage and answer: Household food production can make a modest but useful contribution to nutrition. Even a small balcony or shared plot can supply herbs and vegetables, but success depends on water, soil, time and local climate. Such gardens cannot solve food insecurity by themselves; income, access to markets and public support also matter. Their value is greatest when they complement, rather than replace, broader food systems. What can be inferred about food insecurity?

1. It is caused only by lack of seeds
2. It has causes and solutions beyond simply growing vegetables at home
3. It disappears whenever a balcony exists
4. Markets and income are irrelevant