depends not all rabbits have the same taste mine likes marshmallows
You should be cautious when giving rabbits celery. Celery is very stringy and can interfere with digestion. It is recommended that you cut up the celery into very small pieces before giving it to your rabbit.
yes
It is not bad for rabbits to eat celery. It is healthy for them.
No, it's not necessary to cut up vegetables before giving them to your rabbit, but it should be washed, and rotten bits and white/light-coloured parts (like spines) should be removed. There are some exceptions. Celery, for instance, should be cut up because rabbits sometimes have trouble with the strings that run through the celery; however, celery is a treat, if your rabbit likes it -- it should not be a staple food in your rabbit's diet. Celery greens (dark ones, not light ones) are much better than the celery itself. Rabbits are used to finding their food in its natural form. The rabbit might not even take the food if it's cut up!
carrots and celery
Yes, Yes they can
Test in progress, will get back to you.
Yes
They don't necessarily have a 'favourite' - but their normal diet consists of mice, rats or rabbits (depending on the size of the snake)
Some rabbits have a taste for celery and some don't. You can feed your rabbit celery but if your rabbit doesn't like it, you shouldn't force the rabbit to eat it-- even if its healthy. Celery is a good treat for rabbits. It should be handled as a treat though. A small piece every couple of days is enough.
~Pellets ~Carrots ~Celery ~Lettuce ~Apples
The food color is absorbed by the celery from its roots, whatever color you put in the water affects the color of the celery.