Performed regularly, self-examination can alert you to changes in your skin and aid in the early detection of skin cancer. . . . Look especially for change of any kind. Do not ignore a suspicious spot simply because it does not hurt. Skin cancers may be painless but are dangerous all the same. If you notice one or more of the warning signs, see a doctor right away, preferably one who specializes in diseases of the skin. Warning signs include a skin growth that increases in size and appears pearly, translucent, tan, brown, black, or multicolored; a mole, birthmark, beauty mark, or any brown spot that changes color or size; a mole with an irregular outline; a mole that appears after age 21; and a spot or sore that continues to itch or bleed. – “If You Can Spot It, You Can Stop It,”
Skin Cancer Foundation

According to this passage, which symptoms may be warning signs of skin cancer? Check all that apply.

a sore that does not heal
a painful sunburn
a mole that changes color
a birthmark that is large
a mole with an irregular outline