In regard to suing the federal government in a contract between the government and a contractor

The government cannot be sued under any circumstances due to "governmental immunity"

b$.$ Under certain conditions the government can be sued under the Federal Tort Claims Act

c$.$Corporations cannot sue the government as they are not individual $$entities$$

Under certain conditions the government can be sued under the Federal Tort Claims Act

Corporations cannot sue the government as they are not individual "entities"