Arbitrage arguments:  When the commodity has plentiful supply then the prices can be very well dictated or influenced by Arbitrage arguments. Arbitrage is basically buying in one market and simultaneously selling in another, profiting from a temporary difference. This is considered riskless profit for the investor/trader. For example, if the price of gold in delhi is INR 30,000 per 10 grams and in Mumbai gold price is INR 35,000 then arbitrageur will purchase gold in Delhi and sell in Mumbai
So, call options are also much like insurance - you are paying for a contract that expires at a set time but allows you to purchase a security (like a stock) at a predetermined price (which won't go up even if the price of the stock on the market does). However, you will have to renew your option (typically on a weekly, monthly or quarterly basis). For this reason, options are always experiencing what's called time decay - meaning their value decays over time. 
When buying or selling options, the investor or trader has the right to exercise that option at any point up until the expiration date - so simply buying or selling an option doesn't mean you actually have to exercise it at the buy/sell point. Because of this system, options are considered derivative securities - which means their price is derived from something else (in this case, from the value of assets like the market, securities or other underlying instruments). For this reason, options are often considered less risky than stocks (if used correctly).