grassland
Oatmeal is best to consume for a fiber rich diet. Barley is also good and high in fiber as well as whole grains.
Grains or Vegetables
Obsidian cools so quickly the mineral grains do not have time to form.
The best grains i've found online are from tibicos.org
You best bet is to get "kefir grains" which act as a starter. Find milk grains for milk kefir and water grains for a juice-like kefir drink. The grains are widely available online for purchase. You can often find people sharing them in your community as well.
Since some food from each food group is necessary for good nutrition, there is no "best" food group.
Fruits, vegetables, nuts, and whole grains are the best high fiber foods to eat.
Rats will eat almost anything. It is best to feed them grains.
Whole grains, vegetables, legumes, and some fruit and nuts.
grains
Absolutely not. Fruits and vegetables are probably the best source of fibre.