Purchasing a call option is essentially betting that the price of the share of security (like a stock or index) will go up over the course of a predetermined amount of time. For instance, if you buy a call option for Alphabet (GOOG) at, say, $1,500 and are feeling bullish about the stock, you are predicting that the share price for Alphabet will increase. 
In the case of perishable commodity, the cost of storage is higher than expected future price of a commodity (For ex: TradeINR prefer to sell tomatoes now rather than waiting for 3 more months to get a good price as a cost of storage of tomato is more than price they yield by storing the same). So in this case, the spot prices reflect current supply and demand, not future movements. There spot prices for perishables are more volatile.
The fee you are paying to buy the call option is called the premium (it's essentially the cost of buying the contract which will allow you to eventually buy the stock or security). In this sense, the premium of the call option is sort of like a down-payment like you would place on a house or car. When purchasing a call option, you agree with the seller on a strike price and are given the option to buy the security at a predetermined price (which doesn't change until the contract expires). 
Options are contracts giving the owner the right to buy or sell an asset at a fixed price (called the “strike price”) for a specific period of time. That period of time could be as short as a day or as long as a couple of years, depending on the option. The seller of the option contract has the obligation to take the opposite side of the trade if and when the owner exercises the right to buy or sell the asset. For more information, check out the Ally Invest Options Playbook here: https://www.optionsplaybook.com/

The price at which you agree to buy the underlying security via the option is called the "strike price," and the fee you pay for buying that option contract is called the "premium." When determining the strike price, you are betting that the asset (typically a stock) will go up or down in price. The price you are paying for that bet is the premium, which is a percentage of the value of that asset.