Why does your skin remain red after a bad sunburn? a) Blisters form, lifting the epidermal layer. b) Inflammation causes increased blood flow. c) Loss of sweat glands in the dermal layer d) Damaged epidermis cells are sloughed off.'

Skin remains red after a bad sun burn because:

inflammation causes increased blood flow.

Explanation:

When our skin is exposed to sun rays , the epidermal layer starts getting damaged. The damage to the cell caused by  sun rays triggers the  melanin secretion. Increased secretion of melanin results in darkening of the exposed region .

However, the damage and inflammation to the skin increases blood flow to the skin, this causes reddening of the skin.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.

not always but somethings can be reproduced in a laboratory.