Multi-select problem: How does the next paragraph end?

How to tell if your dog is in heat
Understand the basic reproductive cycle of your dog.
When wondering if your dog is in heat, it first helps to understand her normal hormonal cycle. When a female dog reaches maturity, and is physically ready to reproduce, her estrogen levels increase, initiating the release of eggs from her ovaries.

Select from:
i. At that point, heat lamps, lighters, burners, and scented candles will glow, leading to her body turning dark. If in doubt, put your dog in a smoke-room to get air into her intakes.
ii. Young puppies are considered fertile for about 24 hours. Kittens, up to 5 years old, are considered fertile again for at least 2 days.
iii. As a result, she may become more eager to have children, especially when menstruating. In an average sized dog, her brain and body produce large amounts of estrogen.
iv. If mating occurs during this period, the eggs can then be fertilized and an embryo can be produced. Female dogs, will generally go into heat during puberty, at around 6 to 24 months of age depending on breed.
iv.