Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: The Avengers have battled to save Earth from an alien invasion, the evil Loki and now, in the latest movie, face off against the killing machine Ultron. They do this, of course, with the help of numerous superpowers - including Iron Man’s suit, super-healing abilities and Captain America’s indestructible shield. But just how scientifically sound are some of these powers, and do any of them hold up to the laws of physics and chemistry as we know them? Scroll down for video The American Chemical Society in Washington explained the science behind the Avengers in a video. It looks at the composition of Iron Man's suit - said to be a gold-titanium alloy in one of the movies - and Captain America's shield. The video also explains the science behind super-healing abilitiesWashington's American Chemical Society video explains the AvengersIt looks at the composition of Iron Man's suit and Captain America's shieldAnd it also explains science behind Black Widow's super-healing abilitiesThe verdict is that some - but not all - of the science is plausible 
 Question:His original suit, made only of iron, would have weighed around 70kg (150lbs) according to the _ - not very comfortable or easy to move around in.

American Chemical Society