Certain cereals do indeed have vitamin A in them. Kellogg's Rice Krispies cereal has 25%, so I would check with others that share the Kellogg brand name.
GRAINS!
Carrots are a very good source of vitamin A!
It's likely that grains do have vitamin B. Some grains have 26% of vitamin B, some grains have 15% of vitamin B etc.
Carotene is a good source of vitamin A, according to Switched-On-Schoolhouse (which a homeschooling disk I use).
Vitiman A is good for you
Vitamin C.
Milk is a good source of vitamin D.
No.
The sun
Oranges are a good source of vitamin C.
Yes lemons are a good source of vitaminc
There is no known good natural source of vitamin D other than exposure to sunlight. If needed, there are always Vitamin D supplements, however these aren't as efficiently absorbed compared to the natural source.