White blood cells use "legs" to grab ahold of the blood vessel walls to inch their way forward.
Answer:
Active heating captures sunlight, either as heat or electricity, to augment heating systems, while passive heating captures heat from the sun as it comes into your home through windows, roofs and walls to heat objects in your home (hope that helped?)
Explanation:
I think it is C, but I could be wrong because I am taking an educated guess.
Catalyst maybe ( lower activation energy).
I'm sorry its A..I didn't read it correctly...
