Onion Futures Are Banned in the United States Because

Onion futures are banned in the United States because:

A) onions are perishable
B) some traders manipulated onion futures during the 1950s,and farmers lobbied to pass legislation banning these contracts because they were prone to manipulation
C) onion futures are not useful for price discovery
D) onion futures market attracted too many speculators who destabilized prices and destroyed the market
E) onion futures are not useful to hedgers