Which of the following was key evidence against sacco

The key evidence against Sacco was that one of the bullets was said to have been fired from his gun.

Explanation:

Nicola Sacco was an Italian anarchist who, together with Bartolomeo Vanzetti, was arrested, tried, and electrocuted in Massachusetts on 1927, under the charge of stealing $ 15,766.51 from a shoe factory, the assassination of his accountant named Frederick Parmenter and a security guard named Alessandro Berardelli, despite much doubt of his guilt

The events took place in April 1920, with three berths. Both had alibi, but were the only accused of the crime. With Sacco and Vanzetti the police found weapons and ammunition; however, the ballistics test was confusing, without reaching consensus as to whether the bullets that killed the accountant and his security had departed from the weapon they found with Italian anarchists. The witnesses were also confused and contradictory, which made it even more difficult to find the truth.

B. The author is biased against a law because it would financially  affect his business.

Explanation:

The author of the excerpt is biased. He treats environmental protection laws as if it were a strategy for politicians to end his business. Environmental laws are meant to protect the environment so that we have a comfortable life, but the author of the excerpt only cares about his company's profit and acts as if environmental laws were a bad, selfish thing.

The part of the excerpt that makes this clear is "By limiting the amount of chemicals I can pour into the local river, these politicians are trying to  drive down our productivity and put me out of business!"