What current risks are there to earth from neos?

Asteroid 2003 SD220 is around 1.5 miles wide, and is moving at a speed of 17.5 miles/second. 
It will be approximately 6.7 million miles away from Earth when it passes by. 

The only 'risk' that it poses is negligible, 
and will come from any debris that breaks away from the Asteroid's own gravity, if the debris comes toward us. 

Awoodchuck would chuck all the wood he could chuck if a woodchuck could chuck wood.

The correct answer is  "c".  it is "c" because melting is an endothermic change, and endothermic get's energy from surroundings.